Visual prosthesis

From Wikipedia, the free encyclopedia

A visual prosthesis, often referred to as a bionic eye, is an experimental visual device intended to restore functional vision in those suffering from partial or total blindness. Many devices have been developed, usually modeled on the cochlear implant or bionic ear devices, a type of neural prosthesis in use since the mid-1980s. The idea of using electrical current (e.g., electrically stimulating the retina or the visual cortex) to provide sight dates back to the 18th century, discussed by Benjamin Franklin, Tiberius Cavallo, and Charles LeRoy.

Biological considerations

The ability to give sight to a blind person via a bionic eye depends on the circumstances surrounding the loss of sight. For retinal prostheses, which are the most prevalent visual prosthetic under development (due to ease of access to the retina among other considerations), patients with vision loss due to degeneration of photoreceptors (retinitis pigmentosa, choroideremia, geographic atrophy macular degeneration) are the best candidate for treatment. Candidates for visual prosthetic implants find the procedure most successful if the optic nerve was developed prior to the onset of blindness. Persons born with blindness may lack a fully developed optical nerve, which typically develops prior to birth, though neuroplasticity makes it possible for the nerve, and sight, to develop after implantation.

Technological considerations

Visual prosthetics are being developed as a potentially valuable aid for individuals with visual degradation. Argus II, co-developed at the University of Southern California (USC) Eye Institute and manufactured by Second Sight Medical Products Inc., is now the only such device to have received marketing approval (CE Mark in Europe in 2011). Most other efforts remain investigational; the Retina Implant AG's Alpha IMS won a CE Mark July 2013 and is a significant improvement in resolution. It is not, however, FDA-approved in the US.

Ongoing projects

Argus retinal prosthesis

Mark Humayun, who joined the faculty of the Keck School of Medicine of USC Department of Ophthalmology in 2001; Eugene Dejuan, now at the University of California San Francisco; engineer Howard D. Phillips; bio-electronics engineer Wentai Liu, now at University of California Los Angeles; and Robert Greenberg, now of Second Sight, were the original inventors of the active epi-retinal prosthesis and demonstrated proof of principle in acute patient investigations at Johns Hopkins University in the early 1990s. In the late 1990s the company Second Sight was formed by Greenberg along with medical device entrepreneur, Alfred E. Mann, Their first-generation implant had 16 electrodes and was implanted in six subjects by Humayun at University of Southern California between 2002 and 2004. In 2007, the company began a trial of its second-generation, 60-electrode implant, dubbed the Argus II, in the US and in Europe. In total 30 subjects participated in the studies spanning 10 sites in four countries. In the spring of 2011, based on the results of the clinical study which were published in 2012, Argus II was approved for commercial use in Europe, and Second Sight launched the product later that same year. The Argus II was approved by the United States FDA on 14 February 2013. Three US government funding agencies (National Eye Institute, Department of Energy, and National Science Foundation) have supported the work at Second Sight, USC, UCSC, Caltech, and other research labs.

Microsystem-based visual prosthesis (MIVP)

Designed by Claude Veraart at the University of Louvain, this is a spiral cuff electrode around the optic nerve at the back of the eye. It is connected to a stimulator implanted in a small depression in the skull. The stimulator receives signals from an externally worn camera, which are translated into electrical signals that stimulate the optic nerve directly.

Implantable miniature telescope

Although not truly an active prosthesis, an Implantable Miniature Telescope is one type of visual implant that has met with some success in the treatment of end-stage age-related macular degeneration. This type of device is implanted in the eye's posterior chamber and works by increasing (by about three times) the size of the image projected onto the retina in order to overcome a centrally located scotoma or blind spot.

Created by VisionCare Ophthalmic Technologies in conjunction with the CentraSight Treatment Program, the telescope is about the size of a pea and is implanted behind the iris of one eye. Images are projected onto healthy areas of the central retina, outside the degenerated macula, and is enlarged to reduce the effect the blind spot has on central vision. 2.2x or 2.7x magnification strengths make it possible to see or discern the central vision object of interest while the other eye is used for peripheral vision because the eye that has the implant will have limited peripheral vision as a side effect. Unlike a telescope which would be hand-held, the implant moves with the eye which is the main advantage. Patients using the device may however still need glasses for optimal vision and for close work. Before surgery, patients should first try out a hand-held telescope to see if they would benefit from image enlargement. One of the main drawbacks is that it cannot be used for patients who have had cataract surgery as the intraocular lens would obstruct insertion of the telescope. It also requires a large incision in the cornea to insert.

A Cochrane systematic review seeking to evaluate the effectiveness and safety of the implantable miniature telescope for patients with late or advanced age-related macular degeneration found only one ongoing study evaluating the OriLens intraocular telescope, with results expected in 2020.

Tübingen MPDA Project Alpha IMS

A Southern German team led by the University Eye Hospital in Tübingen, was formed in 1995 by Eberhart Zrenner to develop a subretinal prosthesis. The chip is located behind the retina and utilizes microphotodiode arrays (MPDA) which collect incident light and transform it into electrical current stimulating the retinal ganglion cells. As natural photoreceptors are far more efficient than photodiodes, visible light is not powerful enough to stimulate the MPDA. Therefore, an external power supply is used to enhance the stimulation current. The German team commenced in vivo experiments in 2000, when evoked cortical potentials were measured from Yucatán micropigs and rabbits. At 14 months post implantation, the implant and retina surrounding it were examined and there were no noticeable changes to anatomical integrity. The implants were successful in producing evoked cortical potentials in half of the animals tested. The thresholds identified in this study were similar to those required in epiretinal stimulation. Later reports from this group concern the results of a clinical pilot study on 11 participants suffering from RP. Some blind patients were able to read letters, recognize unknown objects, localize a plate, a cup and cutlery. Two of the patients were found to make microsaccades similar to those of healthy control participants, and the properties of the eye movements depended on the stimuli that the patients were viewing—suggesting that eye movements might be useful measures for evaluating vision restored by implants. In 2010 a new multicenter Study has been started using a fully implantable device with 1500 Electrodes Alpha IMS (produced by Retina Implant AG, Reutlingen, Germany), 10 patients included so far; first results have been presented at ARVO 2011. The first UK implantations took place in March 2012 and were led by Robert MacLaren at the University of Oxford and Tim Jackson at King's College Hospital in London. David Wong also implanted the Tübingen device in a patient in Hong Kong. In all cases previously blind patients had some degree of sight restored.

Harvard/MIT Retinal Implant

Joseph Rizzo and John Wyatt at the Massachusetts Eye and Ear Infirmary and MIT began researching the feasibility of a retinal prosthesis in 1989, and performed a number of proof-of-concept epiretinal stimulation trials on blind volunteers between 1998 and 2000. They have since developed a subretinal stimulator, an array of electrodes, that is placed beneath the retina in the subretinal space and receives image signals beamed from a camera mounted on a pair of glasses. The stimulator chip decodes the picture information beamed from the camera and stimulates retinal ganglion cells accordingly. Their second generation prosthesis collects data and sends it to the implant through RF fields from transmitter coils that are mounted on the glasses. A secondary receiver coil is sutured around the iris.

Artificial silicon retina (ASR)

The brothers Alan Chow and Vincent Chow have developed a microchip containing 3500 photodiodes, which detect light and convert it into electrical impulses, which stimulate healthy retinal ganglion cells. The ASR requires no externally worn devices.

The original Optobionics Corp. stopped operations, but Chow acquired the Optobionics name, the ASR implants and plans to reorganize a new company under the same name. The ASR microchip is a 2mm in diameter silicon chip (same concept as computer chips) containing ~5,000 microscopic solar cells called "microphotodiodes" that each have their own stimulating electrode.

Photovoltaic retinal prosthesis (PRIMA)

Daniel Palanker and his group at Stanford University have developed a photovoltaic retinal prosthesis that includes a subretinal photodiode array and an infrared image projection system mounted on video goggles. Images captured by video camera are processed in a pocket PC and displayed on video goggles using pulsed near-infrared (IR, 880–915 nm) light. These images are projected onto the retina via natural eye optics, and photodiodes in the subretinal implant convert light into pulsed bi-phasic electric current in each pixel. Electric current flowing through the tissue between the active and return electrode in each pixel stimulates the nearby inner retinal neurons, primarily the bipolar cells, which transmit excitatory responses to the retinal ganglion cells. This technology is being commercialized by Pixium Vision (PRIMA), and is being evaluated in a clinical trial (2018). Following this proof of concept, Palanker group is focusing now on developing pixels smaller than 50μm using 3-D electrodes and utilizing the effect of retinal migration into voids in the subretinal implant.

Bionic Vision Australia

An Australian team led by Professor Anthony Burkitt is developing two retinal prostheses. The Wide-View device combines novel technologies with materials that have been successfully used in other clinical implants. This approach incorporates a microchip with 98 stimulating electrodes and aims to provide increased mobility for patients to help them move safely in their environment. This implant will be placed in the suprachoroidal space. Researchers expect the first patient tests to begin with this device in 2013. 

The Bionic Vision Australia consortium is concurrently developing the High-Acuity device, which incorporates a number of new technologies to bring together a microchip and an implant with 1024 electrodes. The device aims to provide functional central vision to assist with tasks such as face recognition and reading large print. This high-acuity implant will be inserted epiretinally. Patient tests are planned for this device in 2014 once preclinical testing has been completed. 

Patients with retinitis pigmentosa will be the first to participate in the studies, followed by age-related macular degeneration. Each prototype consists of a camera, attached to a pair of glasses which sends the signal to the implanted microchip, where it is converted into electrical impulses to stimulate the remaining healthy neurons in the retina. This information is then passed on to the optic nerve and the vision processing centres of the brain. 

The Australian Research Council awarded Bionic Vision Australia a $42 million grant in December 2009 and the consortium was officially launched in March 2010. Bionic Vision Australia brings together a multidisciplinary team, many of whom have extensive experience developing medical devices such as the cochlear implant (or 'bionic ear').

Dobelle Eye

Similar in function to the Harvard/MIT device, except the stimulator chip sits in the primary visual cortex, rather than on the retina. Many subjects have been implanted with a high success rate and limited negative effects. Still in the developmental phase, upon the death of Dobelle, selling the eye for profit was ruled against in favor of donating it to a publicly funded research team.

Intracortical visual prosthesis

The Laboratory of Neural Prosthetics at Illinois Institute Of Technology (IIT), Chicago, is developing a visual prosthetic using intracortical electrode arrays. While similar in principle to the Dobelle system, the use of intracortical electrodes allow for greatly increased spatial resolution in the stimulation signals (more electrodes per unit area). In addition, a wireless telemetry system is being developed to eliminate the need for transcranial wires. Arrays of activated iridium oxide film (AIROF)-coated electrodes will be implanted in the visual cortex, located on the occipital lobe of the brain. External hardware will capture images, process them, and generate instructions which will then be transmitted to implanted circuitry via a telemetry link. The circuitry will decode the instructions and stimulate the electrodes, in turn stimulating the visual cortex. The group is developing a wearable external image capture and processing system to accompany the implanted circuitry. Studies on animals and psyphophysical studies on humans are being conducted to test the feasibility of a human volunteer implant.

History of Tibetan Buddhism

From Wikipedia, the free encyclopedia

Buddhism was first actively disseminated in Tibet from the 7th to the 9th century CE, predominantly from India. During the Era of Fragmentation (9th–10th centuries), Buddhism waned in Tibet, only to rise again in the 11th century. With the Mongol invasion of Tibet in the 13th century and the establishment of the Mongol Yuan dynasty, Tibetan Buddhism spread beyond Tibet to Mongolia and China. From the 14th to the 20th Tibetan Buddhism was patronized by the Chinese Ming dynasty (1368–1644) and the Manchurian Qing dynasty (1644–1912). 

 

The Gelugpa school, founded by Je Tsongkhapa (1357–1419), rose to (political) prominence under Ngawang Lobsang Gyatso (1617–1682), the 5th Dalai Lama, who invited the Mongols to intervene in the Tibetan civil war. The Mongols invested him with the political power of Tibet, leading to the dominance of the Gelugpa until the 20th century. In the 19th century the Rimé movement provided a counter-weight against this dominance, trying to preserve the teachings of the Nyingma, Kagyu and Sakya schools.

In the early 20th century Tibet acquired de facto independence from the Manchurian Qing Empire, which ended again with the Chinese invasion of 1950 and the ensuing exodus of Tibetans. Today, Tibetan Buddhism is still adhered to in the Tibetan Plateau and surrounding regions, while it has also attracted a considerable interest in the Western world.

Legendary origins (5th–7th centuries)

According to tradition, in the reign of King Thothori Nyantsen (5th century), a basket of Buddhist scriptures arrived in Tibet from India.^{[note 2]}

First dissemination (7th–9th centuries)

Songtsän Gampo (7th century)

Sanskrit Buddhist scriptures from Nepal & India were first translated into Tibetan under the reign of the Tibetan king Songtsän Gampo (618-649), who established the Tibetan Empire. While there is doubt about the level of Songtsän Gampo's interest in Buddhism, it is known that he married a Chinese Tang Dynasty Buddhist princess, Wencheng, who came to Tibet with a statue of Shakyamuni Buddha. It is clear from Tibetan sources that some of his successors became ardent Buddhists. The records show that Chinese Buddhists were actively involved in missionary activity in Tibet, but they did not have the same level of imperial support as Indian Buddhists, with tantric lineages from Bihar and Bengal.

According to a Tibetan legendary tradition, Songtsän Gampo also married a Nepalese Buddhist princess, Bhrikuti. By the second half of the 8th century he was already regarded as an embodiment of the Bodhisattva Avalokiteśvara.

Indian and Nepalese influences (8th century)

Padmasambhāva, founder of the Nyingmapa, the earliest school of Tibetan Buddhism; note the wide-open eyes, characteristic of a particular method of meditation

 

In the 8th century Buddhism really took hold in Tibet. The successors of Songtsän Gampo were less enthusiastic about the propagation of Buddhism, but in the 8th century King Trisong Detsen (755–797) established it as the official religion of the state.

Trisong Detsen invited Indian Buddhist scholars to his court, and Tibetan Buddhists today trace their oldest spiritual roots to the Indian masters Padmasambhāva (8th century) and Śāntarakṣita (725–788), who founded the Nyingma, The Ancient Ones, the oldest school of Tibetan Buddhism. According to Tibetan tradition, Padmasambhāva wrote a number of important scriptures, some of which he hid for future tertons to find; these Terma "treasures" (revealed texts) are of particular significance to the Nyingma school. 

At this early time also, from the south came the influence of scholars under the Pāla dynasty in the Indian state of Magadha. They had achieved a blend of Mahāyāna and Vajrayāna that has come to characterize all forms of Tibetan Buddhism. Their teaching in sutra centered on the Abhisamayālankāra, a 4th-century Yogācārin text, but prominent among them were the Mādhyamika scholars Śāntarakṣita and Kamalaśīla. 

A third influence was that of the Sarvāstivādins from Kashmir to the southwest and Khotan to the northwest. Although they did not succeed in maintaining a presence in Tibet, their texts found their way into the Tibetan Buddhist canon, providing the Tibetans with almost all of their primary sources about what they regarded to be the Hinayana. A subsect of this school, Mūlasarvāstivāda was the source of the Tibetan vinaya.

Chinese influences (8th century)

The Chinese princess Jincheng Gongzhu (zh:金城公主) (?–739), known in Tibet as Kim-sheng, and a devout Buddhist, was sent to Tibet in 710 where she married Mes-ag-tshoms. Buddhist monks from Khotan (Li), fleeing the persecutions of an anti-Buddhist king, were given refuge by Kim-sheng about 737. Kim-sheng died during an outbreak of smallpox sometime between 739 and 741, and anti-Buddhist factions in Tibet began to blame the epidemic on the support of Buddhism by the king and queen. This forced the monks to flee once again; first to Gandhara, and then to Kosambi in central India where the monks apparently ended up quarrelling and slaughtering each other.

Tibetan king Trisong Detsen (742–797) invited the Chan master Moheyan to transmit the Dharma at Samye Monastery. According to Tibetan sources, Moheyan lost the socalled council of Lhasa (793), a debate sponsored by Trisong Detsen on the nature of emptiness with the Indian master Kamalaśīla, and the king declared Kamalaśīlas philosophy should form the basis for Tibetan Buddhism. However, a Chinese source found in Dunhuang written by Mo-ho-yen says their side won, and some scholars conclude that the entire episode is fictitious.

Pioneering Buddhologist Giuseppe Tucci speculated that Mohayen's ideas were preserved by the Nyingmapas in the form of dzogchen teachings. John Myrdhin Reynolds and Sam van Schaik reject this possibility. According to Reynolds, "Except for a brief flirtation with Ch'an in the early days of Buddhism in Tibet in the eighth century, the Tibetans exhibited almost no interest at all in Chinese Buddhism, except for translating a few Sutras from Chinese for which they did not possess Indian originals."

Growth in Tibet (9th century)

From the outset Buddhism was opposed by the native shamanistic Bön religion, which had the support of the aristocracy, but it thrived under royal patronage, reaching a peak under King Rälpachän (r. 817–836). Terminology in translation was standardised around 825, enabling a highly literal translation methodology.

Era of fragmentation (9th–10th centuries)

A reversal in Buddhist influence began under King Langdarma (r. 836–842), and his death was followed by the socalled Era of Fragmentation, a period of Tibetan history in the 9th and 10th centuries. During this era, the political centralization of the earlier Tibetan Empire collapsed. The period was dominated by rebellions against the remnants of imperial Tibet and the rise of regional warlords. Upon the death of Langdarma, the last emperor of a unified Tibetan empire, a civil war ensued, which effectively ended centralized Tibetan administration until the Sa-skya period. Ösung's allies managed to keep control of Lhasa, and Yumtän was forced to go to Yalung, where he established a separate line of kings.

Tibetan Renaissance (10th–12th centuries)

Atiśa

The late 10th and 11th century saw a revival of Buddhism in Tibet. Coinciding with the early discoveries of "hidden treasures" (terma), the 11th century saw a revival of Buddhist influence originating in the far east and far west of Tibet. In the west, Rinchen Zangpo (958-1055) was active as a translator and founded temples and monasteries. Prominent scholars and teachers were again invited from India. 

In 1042 Atiśa (982–1054 CE) arrived in Tibet at the invitation of a west Tibetan king. This renowned exponent of the Pāla form of Buddhism from the Indian university of Vikramashila later moved to central Tibet. There his chief disciple, Dromtonpa founded the Kadampa school of Tibetan Buddhism, under whose influence the New Translation schools of today evolved. 

The Sakya, the Grey Earth school, was founded by Khön Könchok Gyelpo (Wylie: 'khon dkon mchog rgyal po, 1034–1102), a disciple of the great Lotsawa, Drogmi Shākya (Wylie: brog mi lo tsā wa ye shes). It is headed by the Sakya Trizin, traces its lineage to the mahasiddha Virūpa, and represents the scholarly tradition. A renowned exponent, Sakya Pandita (1182–1251CE), was the great-grandson of Khön Könchok Gyelpo.

Other seminal Indian teachers were Tilopa (988–1069) and his student Naropa (probably died ca. 1040 CE).The Kagyu, the Lineage of the (Buddha's) Word, is an oral tradition which is very much concerned with the experiential dimension of meditation. Its most famous exponent was Milarepa, an 11th-century mystic. It contains one major and one minor subsect. The first, the Dagpo Kagyu, encompasses those Kagyu schools that trace back to the Indian master Naropa via Marpa Lotsawa, Milarepa and Gampopa

Mongol dominance (13th–14th centuries)

Initial influence on Mongolia (11th–13th centuries)

Tibetan Buddhism exerted a strong influence from the 11th century CE among the peoples of Inner Asia, especially the Mongols. Tantric-style Tibetan Buddhism was possibly first spread to the Mongols via the Tangut state of Western Xia (1038–1227). Buddhists entered the service of the Mongol Empire in the early 13th century. Buddhist monasteries established in Karakorum were granted tax exempt status, though the religion was not given official status by the Mongols until later.

Mongol conquest of Tibet (13th century)

The Mongols invaded Tibet in 1240. The Mongols withdrew their soldiers from Tibet in 1241, and returned to the region in 1244, when Köten delivered an ultimatum, summoning the abbot of Sakya (Kun-dga' rGyal-mtshan) to be his personal chaplain, on pains of a larger invasion were he to refuse. Sakya Paṇḍita took almost 3 years to obey the summons and arrive in the Kokonor region in 1246, and met Prince Köten in Liangzhou the following year. The Mongols had annexed Amdo and Kham to the east, and appointed Sakya Paṇḍita Viceroy of Central Tibet by the Mongol court in 1249.

Tibet was incorporated into the Mongol Empire, retaining nominal power over religious and regional political affairs, while the Mongols managed a structural and administrative rule over the region, reinforced by the rare military intervention.

Yuan dynasty (1271–1368)

Tibetan Buddhism was adopted as the de facto state religion by the Mongol Yuan dynasty (1271–1368), founded by Kublai Khan, that also ruled China.

All variants of Buddhism, such as Chinese, Tibetan and Indian Buddhism flourished, though Tibetan Buddhism was eventually favored at the imperial level under emperor Möngke (1209-1259), who appointed Namo from Kashmir as chief of all Buddhist monks. The top-level department and government agency known as the Bureau of Buddhist and Tibetan Affairs (Xuanzheng Yuan) was set up in Khanbaliq (modern-day Beijing) to supervise Buddhist monks throughout the empire. The Sakya Imperial Preceptors were active at the Yuan court and enjoyed special power. During this period Tibetan Buddhism was practiced not only within the capital Beijing and the Tibetan Plateau, but throughout the country. For instance, Hangzhou, capital of the former Southern Song dynasty and the largest city in the Yuan realm, became an important hub of the activities of Tibetan Buddhism, which took public or official precedence over Han Chinese Buddhism. Similarly, Mount Wutai, the sacred site of Bodhisattva Manjusri and the holy mountain of Chinese Buddhist pilgrims, was greatly influenced by Tibetan Buddhism.

Decline of the Golden Horde and the Ilkhanate (13th–14th centuries)

Among the ruling class of the Mongol khanates of the Golden Horde (1240s–1502) and the Ilkhanate (1256–1335/1353), the two western khanates of the Mongol Empire, Shamanism and Buddhism were once the dominant religions, as in the Yuan dynasty. In the early days, the rulers of both khanates increasingly adopted Tibetan Buddhism, like the Yuan dynasty at that time. However, the Mongol rulers Ghazan of the Ilkhanate and Uzbeg of the Golden Horde converted to Islam in AD 1295 and AD 1313 respectively. The Yuan dynasty based in China and Mongolia became the only division of the Mongol Empire not to embrace Islam, instead favoring Tibetan Buddhism until its demise.

Tibetan independence (14th–18th centuries)

With the decline of the Yuan dymansty, Central Tibet was to ruled by successive families from the 14th to the 17th century, and Tibet would be de facto independent from the mid-14th century on, for nearly 400 years.

Family rule and establishment of Gelugpa school (14th–17th centuries)

Jangchub Gyaltsän (Byang chub rgyal mtshan, 1302–1364) became the strongest political family in the mid 14th century. Military hostilities ended in 1354 with Jangchub Gyaltsän as the unquestioned victor, who established the Phagmodrupa Dynasty in that year. He continued to rule central Tibet until his death in 1364, although he left all Mongol institutions in place as hollow formalities. Power remained in the hands of the Phagmodru family until 1434.

The rule of Jangchub Gyaltsän and his successors implied a new cultural self-awareness where models were sought in the age of the ancient Tibetan Kingdom. The relatively peaceful conditions favoured the literary and artistic development.^[43] During this period the reformist scholar Je Tsongkhapa (1357–1419) founded the Gelug sect which would have a decisive influence on Tibet's history.

Internal strife within the Phagmodrupa dynasty, and the strong localism of the various fiefs and political-religious factions, led to a long series of internal conflicts. The minister family Rinpungpa, based in Tsang (West Central Tibet), dominated politics after 1435.

In 1565 the Rinpungpa family was overthrown by the Tsangpa Dynasty of Shigatse which expanded its power in different directions of Tibet in the following decades and favoured the Karma Kagyu sect. They would play a pivotal role in the events which led to the rise of power of the Dalai Lama's in the 1640s.

Ming patronage

Tibet

In spite of the weakening of central authority, the neighbouring Ming Dynasty of China (1368–1644) made little effort to impose direct rule, although it had nominal claims of the Tibetan territory by establishing the U-Tsang Regional Military Commission and Do-Kham Regional Military Commission in the 1370s. Tibetan Buddhism was patronized by the ethnic-Chinese Ming dynasty that succeeded the Yuan, and kept friendly relations with some of the Buddhism religious leaders known as Princes of Dharma and granted some other titles to local leaders including the Grand Imperial Tutor.

Mongolia

The Ming dynasty (1368–1644) rulers deliberately helped propagate Tibetan Buddhism instead of Chinese Buddhism among the Mongols. During the early period of the Northern Yuan dynasty (1368-ca.1636), shamanism once again became the sole dominant religion in Mongolia, but the last sixty years before the death of the last khan Ligdan Khan (1588-1643) were marked by intensive penetration of Tibetan Buddhism into Mongolian society. In 1578, Sonam Gyatso was invited to Mongolia and converted Altan Khan to Buddhism along with his tribe (the first Mongol tribe to be so converted). Altan Khan conferred the title "Dalai" on him, "Dalai" being the Mongolian translation of his Tibetan name "Gyatso", which means "sea" or "ocean". This is the origin of the title Dalai Lama. The Ming assisted Altan Khan (1507–1582), King of the Tümed Mongols, when he requested aid in propagating Lamaism. Within 50 years nearly all the Mongols had become Buddhists, including tens of thousands of monks, almost all followers of the Gelug school and loyal to the Dalai Lama. Since then Tibetan Buddhism has played a very important role among the Mongols. 

Tibetan Buddhism was the most important religion among the Mongols under Qing rule (1635–1912), as well as the state religion of the Kalmyk Khanate (1630–1771), the Dzungar Khanate (1634–1758) and the Khoshut Khanate (1642–1717). Tibetan Buddhism was also adored by the Qing court (1644–1912) since both Mongols and Tibetans believed in Tibetan Buddhism.

Some historians view the promotion of Lamaist Buddhism among the Mongols by the Ming and Qing as a deliberate plot to weaken the Mongol's military prowess, but others reject the theory.

Ganden Phodrang government (17th–18th centuries)

The Ganden Phodrang was the Tibetan regime or government that was established by the 5th Dalai Lama with the help of the Güshi Khan of the Khoshut in 1642. After the civil war in the 17th century and the Mongol intervention, the Gelugpa school dominated Tibetan Buddhism, and successive Dalai Lamas ruled Tibet from the mid-17th to mid-20th centuries.

Beginnings of the Dalai Lama lineage

The rise of the Dalai Lama's was intimately connected with the military power of Mongolian clans. Altan Khan, the king of the Tümed Mongols, first invited Sonam Gyatso, the head of the Gelugpa school of Tibetan Buddhism (later known as the third Dalai Lama), to Mongolia in 1569 and again in 1578, during the reign of the Tsangpa family. Gyatso accepted the second invitation. They met at the site of Altan Khan's new capital, Koko Khotan (Hohhot), and the Dalai Lama taught a huge crowd there.

Sonam Gyatso publicly announced that he was a reincarnation of the Tibetan Sakya monk Drogön Chögyal Phagpa (1235–1280) who converted Kublai Khan, while Altan Khan was a reincarnation of Kublai Khan (1215–1294), the famous ruler of the Mongols and Emperor of China, and that they had come together again to cooperate in propagating the Buddhist religion. While this did not immediately lead to a massive conversion of Mongols to Buddhism (this would only happen in the 1630s), it did lead to the widespread use of Buddhist ideology for the legitimation of power among the Mongol nobility. Last but not least, Yonten Gyatso, the fourth Dalai Lama, was a grandson of Altan Khan.

Rise and dominance of Gelugpa (17th–18th centuries)

Sonam Choephel (1595–1657 CE), the first regent of the fifth Dalai Lama, was "the prime architect of the Gelug's rise to power". Sonam Choephel requested the aid of Güshi Khan, a powerful Dzungar military leader to end decades of clan-wars in Dbus and Gtsang privinces, and the Tibetan civil war of 1639-1642. Güshi Khan (who was head of the Khoshut tribe) conquered Kham in 1640 bringing the Sakyas and the lords of Kham and Amdo under their control. His victory over Karma Tenkyong, the prince of Tsang in Shigatse, in 1642, completed the military unification of the country and the establishment of the Khoshut Khanate. By this feat the Phagmodrupa Dynasty, which was associated with a variant of the Kagyu school, was technically replaced; in actual fact it had been powerless for many years. By subsequently formally recognizing the Fifth Dalai Lama's authority in 1642, Güshi Khan effectively made Gyatso the temporal ruler of all Tibet.

Qing rule (18th–20th centuries)

Establishment of Qing rule

The Qing dynasty (1644–1912) established their rule over Tibet after a Qing expedition force defeated the Dzungars in 1720, and lasted until the fall of the Qing dynasty in 1912. The Qing emperors appointed imperial residents known as the Ambans to Tibet, who commanded over 2,000 troops stationed in Lhasa and reported to the Lifan Yuan, a Qing government agency that oversaw the region during this period. The rulers of the Manchu Qing dynasty supported Tibetan Buddhism, especially the Gelug sect, for most of their dynasty.

Rimé movement (19th century)

The Rimé movement was a movement involving the Sakya, Kagyu and Nyingma schools of Tibetan Buddhism, along with some Bon scholars. Having seen how the Gelug institutions pushed the other traditions into the corners of Tibet's cultural life, Jamyang Khyentse Wangpo (1820–1892) and Jamgön Kongtrül (1813–1899) compiled together the teachings of the Sakya, Kagyu and Nyingma, including many near-extinct teachings. Without Khyentse and Kongtrul's collecting and printing of rare works, the suppression of Buddhism by the Communists would have been much more final.^[60] The Rimé movement is responsible for a number of scriptural compilations, such as the Rinchen Terdzod and the Sheja Dzö.

Modern history (20th–21st centuries)

20th century – de facto independence, Chinese occupation, and Tibetan exodus

In 1912 Tibet became de facto independent again, but was annexed by the Chinese People's republic in 1950. In 1959 the 14th Dalai Lama and a great number of clergy fled the country, to settle in India and other neighbouring countries. This also started the spread of Tibetan Buddhism to western countries, resulting in worldwide communities of Tibetan Buddhism.

21st century – exile and spread abroad

Today, Tibetan Buddhism is adhered to widely in the Tibetan Plateau, Mongolia, northern Nepal, Kalmykia (on the north-west shore of the Caspian), Siberia (Tuva and Buryatia), the Russian Far East and northeast China. It is the state religion of Bhutan. The Indian regions of Sikkim and Ladakh, both formerly independent kingdoms, are also home to significant Tibetan Buddhist populations, as are the Indian states of Himachal Pradesh (which includes Dharamshala and the district of Lahaul-Spiti), West Bengal (the hill stations of Darjeeling and Kalimpong) and Arunachal Pradesh. 

In the wake of the Tibetan diaspora, Tibetan Buddhism has gained adherents in the West and throughout the world. Fully ordained Tibetan Buddhist Monks now work in academia (for example Ven. Alex Bruce ('Tenpa')). The 14th Dalai Lama, Tenzin Gyatso, has traveled the world and spoken about the welfare of Tibetans, environment, economics, women's rights, non-violence, interfaith dialogue, physics, astronomy, Buddhism and science, cognitive neuroscience, reproductive health, and sexuality, along with various Mahayana and Vajrayana topics. He received the Nobel Peace Prize in 1989.

Smartglasses

From Wikipedia, the free encyclopedia

Using the touch pad built on the side of the 2013 Google Glass to communicate with the user's phone using Bluetooth.

 

Man wearing a 1998 EyeTap, Digital Eye Glass.

Smartglasses or smart glasses are wearable computer glasses that add information alongside or to what the wearer sees. Alternatively smartglasses are sometimes defined as wearable computer glasses that are able to change their optical properties at runtime. Smart sunglasses which are programmed to change tint by electronic means are an example of the latter type of smartglasses. Superimposing information onto a field of view is achieved through an optical head-mounted display (OHMD) or embedded wireless glasses with transparent heads-up display (HUD) or augmented reality (AR) overlay that has the capability of reflecting projected digital images as well as allowing the user to see through it, or see better with it. While early models can perform basic tasks, such as just serve as a front end display for a remote system, as in the case of smartglasses utilizing cellular technology or Wi-Fi, modern smart glasses are effectively wearable computers which can run self-contained mobile apps. Some are handsfree that can communicate with the Internet via natural language voice commands, while other use touch buttons.

Like other computers, smartglasses may collect information from internal or external sensors. It may control or retrieve data from other instruments or computers. It may support wireless technologies like Bluetooth, Wi-Fi, and GPS. While a smaller number of models run a mobile operating system and function as portable media players to send audio and video files to the user via a Bluetooth or WiFi headset. Some smartglasses models, also feature full lifelogging and activity tracker capability.

Such smartglasses devices may also have all the features of a smartphone. Some also have activity tracker functionality features (also known as "fitness tracker") as seen in some GPS watches.

Features and applications

As with other lifelogging and activity tracking devices, the GPS tracking unit and digital camera of some smartglasses can be used to record historical data. For example, after the completion of a workout, data can be uploaded onto a computer or online to create a log of exercise activities for analysis. Some smart watches can serve as full GPS navigation devices, displaying maps and current coordinates. Users can "mark" their current location and then edit the entry's name and coordinates, which enables navigation to those new coordinates.

Although some smartglasses models manufactured in the 21st century are completely functional as standalone products, most manufacturers recommend or even require that consumers purchase mobile phone handsets that run the same operating system so that the two devices can be synchronized for additional and enhanced functionality. The smartglasses can work as an extension, for head-up display (HUD) or remote control of the phone and alert the user to communication data such as calls, SMS messages, emails, and calendar invites.

Security applications

Smart glasses could be used as a body camera. In 2018, Chinese police in Zhengzhou and Beijing were using smart glasses to take photos which are compared against a government database using facial recognition to identify suspects, retrieve an address, and track people moving beyond their home areas.

Healthcare applications

Several proofs of concept for Google Glasses have been proposed in healthcare. In July 2013, Lucien Engelen started research on the usability and impact of Google Glass in health care. Engelen, who is based at Singularity University and in Europe at Radboud University Medical Center, is participating in the Glass Explorer program.

Key findings of Engelen's research included:

1. The quality of pictures and video are usable for healthcare education, reference, and remote consultation.The camera needs to be tilted to different angle for most of the operative procedures
2. Tele-consultation is possible—depending on the available bandwidth—during operative procedures.
3. A stabilizer should be added to the video function to prevent choppy transmission when a surgeon looks to screens or colleagues.
4. Battery life can be easily extended with the use of an external battery.
5. Controlling the device and/or programs from another device is needed for some features because of sterile environment.
6. Text-to-speech ("Take a Note" to Evernote) exhibited a correction rate of 60 percent, without the addition of a medical thesaurus.
7. A protocol or checklist displayed on the screen of Google Glass can be helpful during procedures.

Dr. Phil Haslam and Dr. Sebastian Mafeld demonstrated the first concept for Google Glass in the field of interventional radiology. They demonstrated the manner in which the concept of Google Glass could assist a liver biopsy and fistulaplasty, and the pair stated that Google Glass has the potential to improve patient safety, operator comfort, and procedure efficiency in the field of interventional radiology. In June 2013, surgeon Dr. Rafael Grossmann was the first person to integrate Google Glass into the operating theater, when he wore the device during a PEG (percutaneous endoscopic gastrostomy) procedure. In August 2013, Google Glass was also used at Wexner Medical Center at Ohio State University. Surgeon Dr. Christopher Kaeding used Google Glass to consult with a colleague in a distant part of Columbus, Ohio. A group of students at The Ohio State University College of Medicine also observed the operation on their laptop computers. Following the procedure, Kaeding stated, "To be honest, once we got into the surgery, I often forgot the device was there. It just seemed very intuitive and fit seamlessly."

The November 16, 2013, in Santiago de Chile, the maxillofacial team led by Dr.gn Antonio Marino conducted the first orthognathic surgery assisted with Google Glass in Latin America, interacting with them and working with simultaneous three-dimensional navigation. The surgical team was interviewed by the ADN radio and the LUN newspaper. In January 2014, Indian Orthopedic Surgeon Selene G. Parekh conducted the foot and ankle surgery using Google Glass in Jaipur, which was broadcast live on Google website via the internet. The surgery was held during a three-day annual Indo-US conference attended by a team of experts from the US, and co-organized by Ashish Sharma. Sharma said Google Glass allows looking at an X-Ray or MRI without taking the eye off of the patient, and allows a doctor to communicate with a patient's family or friends during a procedure.

Baby Eve with Georgia for the Breastfeeding Support Project

 

In Australia, during January 2014, Melbourne tech startup Small World Social collaborated with the Australian Breastfeeding Association to create the first hands-free breastfeeding Google Glass application for new mothers. The application, named Google Glass Breastfeeding app trial, allows mothers to nurse their baby while viewing instructions about common breastfeeding issues (latching on, posture etc.) or call a lactation consultant via a secure Google Hangout, who can view the issue through the mother's Google Glass camera. The trial was successfully concluded in Melbourne in April 2014, and 100% of participants were breastfeeding confidently.

Display types

Various techniques have existed for see-through HMDs. Most of these techniques can be summarized into two main families: “Curved Mirror” (or Curved Combiner) based and “Waveguide” or "Light-guide" based. The mirror technique has been used in EyeTaps, by Meta in their Meta 1, by Vuzix in their Star 1200 product, by Olympus, and by Laster Technologies. 

Various waveguide techniques have existed for some time. These techniques include diffraction optics, holographic optics, polarized optics, reflective optics, and projection:

• Diffractive waveguide – slanted diffraction grating elements (nanometric 10E-9). Nokia technique now licensed to Vuzix.
• Holographic waveguide – 3 holographic optical elements (HOE) sandwiched together (RGB). Used by Sony and Konica Minolta.
• Reflective waveguide – thick light guide with single semi reflective mirror. This technique is used by Epson in their Moverio product.
• Virtual retinal display (VRD) – Also known as a retinal scan display (RSD) or retinal projector (RP), is a display technology that draws a raster display (like a television) directly onto the retina of the eye - developed by MicroVision, Inc.

The Technical Illusions castAR uses a different technique with clear glass. The glasses have a projector, and the image is returned to the eye by a reflective surface.

Smart sunglasses

Smart sunglasses which are able to change their light filtering properties at runtime generally use liquid crystal technology. As lighting conditions change, for example when the user goes from indoors to outdoors, the brightness ratio also changes and can cause undesirable vision impairment. An attractive solution for overcoming this issue is to incorporate dimming filters into smart sunglasses which control the amount of ambient light reaching the eye. An innovative liquid crystal based component for use in the lenses of smart sunglasses is PolarView by LC-Tec. PolarView offers analog dimming control, with the level of dimming being adjusted by an applied drive voltage. 

Another type of smart sunglasses uses adaptive polarization filtering (ADF). ADF-type smart sunglasses can change their polarization filtering characteristics at runtime. For example, ADF-type smart sunglasses can change from horizontal polarization filtering to vertical polarization filtering at the touch of a button.

The lenses of smart sunglasses can be manufactured out of multiple adaptive cells, therefore different parts of the lens can exhibit different optical properties. For example the top of the lens can be electronically configured to have different polarization filter characteristics and different opacity than the lower part of the lens.

Human Computer Interface (HCI) control input

Head-mounted displays are not designed to be workstations, and traditional input devices such as keyboard and mouse do not support the concept of smartglasses. Instead Human Computer Interface (HCI) control input needs to be methods lend themselves to mobility and/or hands-free use are good candidates, for example:

• Touchpad or buttons
• Compatible devices (e.g. smartphones or control unit) for remote control
• Speech recognition
• Gesture recognition
• Eye tracking
• Brain–computer interface

Notable products

In development

• AMA Xperteye - Advanced Mobile Applications (AMA Studios) software for off the shelf customizable smart glasses interface
• b.g. (Beyond Glasses) by Meganesuper Co., Ltd. – adjustable wearable display than can be attached to regular prescription glasses
• castAR by Technical Illusions – wearable AR device for gaming

Current

• Airscouter, a virtual retinal display made by Brother Industries
• Epiphany Eyewear - smart glasses developed by Vergence Labs, a subsidiary of Snap Inc.
• Epson Moverio BT-300 and Moverio Pro BT-2000/2200 – augmented reality smartglasses by Epson.
• Everysight Raptor – smart glasses for cyclists.
• EyeTap – eye-mounted camera and head-up display (HUD).
• Golden-i Infinity – a wearable smart screen for Android or Win10 host devices.
• Google Glass – optical head-mounted display.
• Magic Leap
• Microsoft HoloLens - a pair of mixed reality smart glasses with high-definition 3D optical head-mounted display and spatial sound developed and manufactured by Microsoft, using the Windows Holographic platform.
• Pivothead SMART – "Simple Modular Application-Ready Technology", released in October 2014
• SixthSense – wearable AR device.
• Spectacles - sunglasses with an embedded wearable camera by Snap Inc.
• Vuzix – Augmented reality glasses for 3D gaming, manufacturing training, and military applications.

Discontinued

• Looxcie – ear-mounted streaming video camera

2010s

2012

• On 17 April 2012, Oakley's CEO Colin Baden stated that the company has been working on a way to project information directly onto lenses since 1997, and has 600 patents related to the technology, many of which apply to optical specifications.
• On 18 June 2012, Canon announced the MR (Mixed Reality) System which simultaneously merges virtual objects with the real world at full scale and in 3D. Unlike the Google Glass, the MR System is aimed for professional use with a price tag for the headset and accompanying system is $125,000, with $25,000 in expected annual maintenance.

2013

• At MWC 2013, the Japanese company Brilliant Service introduced the Viking OS, an operating system for HMD's which was written in Objective-C and relies on gesture control as a primary form of input. It includes a facial recognition system and was demonstrated on a revamp version of Vuzix STAR 1200XL glasses ($4,999) which combined a generic RGB camera and a PMD CamBoard nano depth camera.
• At Maker Faire 2013, the startup company Technical Illusions unveiled CastAR augmented reality glasses which are well equipped for an AR experience: infrared LEDs on the surface detect the motion of an interactive infrared wand, and a set of coils at its base are used to detect RFID chip loaded objects placed on top of it; it uses dual projectors at a frame rate of 120 Hz and a retro reflective screen providing a 3D image that can be seen from all directions by the user; a camera sitting on top of the prototype glasses is incorporated for position detection, thus the virtual image changes accordingly as a user walks around the CastAR surface.
• At D11 Conference 2013, the startup company Atheer Labs unveild its 3D augmented reality glasses prototype. The prototype includes binicular lens, 3D images support, a rechargeable battery, WiFi, Bluetooth 4.0, accelerometer, gyro and an IR. User can interact with the device by voice commands and the mounted camera allows the users to interact naturally with the device with gestures.

2014

• The Orlando Magic, Indiana Pacers, and other NBA teams used Google Glass on the CrowdOptic platform to enhance the in-game experience for fans.
• Rhode Island Hospital's Emergency Department became the first emergency department to experiment with Google Glass applications.

2018

• Intel announces Vaunt, a set of smart glasses that are designed to appear like conventional glasses and are display-only, using retinal projection.

Market structure

Analytics company IHS has estimated that the shipments of smart glasses may rise from just 50,000 units in 2012 to as high as 6.6 million units in 2016. According to a survey of more than 4,600 U.S. adults conducted by Forrester Research, around 12 percent of respondents are willing to wear Google Glass or other similar device if it offers a service that piques their interest. Business Insider's BI Intelligence expects an annual sales of 21 million Google Glass units by 2018. Samsung and Microsoft are expected to develop their own version of Google Glass within six months with a price range of $200 to $500. Samsung has reportedly bought lenses from Lumus, a company based in Israel. Another source says Microsoft is negotiating with Vuzix. In 2006, Apple filed patent for its own HMD device. In July 2013, APX Labs founder and CEO Brian Ballard stated that he knows of 25 to 30 hardware companies which are working on their own versions of smartglasses, some of which APX is working with.

In fact, there were only about 150K AR glasses shipped to customers through the world in 2016 despite strong opinion of CEOs of leading tech companies that AR is entering our life. This outlines some serious technical limitations that prevent OEMs from offering a product that would balance functionality and customers’ desire not to wear daily a massive facial/cephalic device. The solution could be in transfer of battery, processing power and connectivity from the AR glasses frame to an external wire-connected device such as smart necklace. This could allow development of AR glasses serving as display only – lite, cheap and stylish.

Public reception for commercial usage

Critical reception

In November 2012, Google Glass received recognition by Time Magazine as one of the "Best Inventions of the Year 2012", alongside inventions such as the Curiosity Rover. After a visit to the University of Cambridge by Google's chairman Eric Schmidt in February 2013, Wolfson College professor John Naughton praised the Google Glass and compared it with the achievements of hardware and networking pioneer Douglas Engelbart. Naughton wrote that Engelbart believed that machines "should do what machines do best, thereby freeing up humans to do what they do best". Lisa A. Goldstein, a freelance journalist who was born profoundly deaf, tested the product on behalf of people with disabilities and published a review on August 6, 2013. In her review, Goldstein states that Google Glass does not accommodate hearing aids and is not suitable for people who cannot understand speech. Goldstein also explained the limited options for customer support, as telephone contact was her only means of communication.

In December 2013, David Datuna became the first artist to incorporate Google Glass into a contemporary work of art. The artwork debuted at a private event at The New World Symphony in Miami Beach, Florida, US and was moved to the Miami Design District for the public debut. Over 1500 people used Google Glass to experience Datuna's American flag from his "Viewpoint of Billions" series.

After negative public reaction, the retail availability of Google Glass ended in January 2015, and the company moved to focus on business customers in 2017.

Privacy concerns

The EyeTap's functionality and minimalist appearance have been compared to Steve Mann's EyeTap, also known as "Glass" or "Digital Eye Glass", although Google Glass is a "Generation-1 Glass" compared to EyeTap, which is a "Generation-4 Glass". According to Mann, both devices affect both privacy and secrecy by introducing a two-sided surveillance and sousveillance. Concerns have been raised by various sources regarding the intrusion of privacy, and the etiquette and ethics of using the device in public and recording people without their permission. There is controversy that Google Glass would violate privacy rights due to security problems and others.

Privacy advocates are concerned that people wearing such eyewear may be able to identify strangers in public using facial recognition, or surreptitiously record and broadcast private conversations. Some companies in the U.S. have posted anti-Google Glass signs in their establishments. In July 2013, prior to the official release of the product, Stephen Balaban, co-founder of software company Lambda Labs, circumvented Google’s facial recognition app block by building his own, non-Google-approved operating system. Balaban then installed face-scanning Glassware that creates a summary of commonalities shared by the scanned person and the Glass wearer, such as mutual friends and interests. Additionally, Michael DiGiovanni created Winky, a program that allows a Google Glass user to take a photo with a wink of an eye, while Marc Rogers, a principal security researcher at Lookout, discovered that Glass can be hijacked if a user could be tricked into taking a picture of a malicious QR code.

Other concerns have been raised regarding legality of Google Glass in a number of countries, particularly in Russia, Ukraine, and other post-USSR countries. In February 2013, a Google+ user noticed legal issues with Google Glass and posted in the Google Glass community about the issues, stating that the device may be illegal to use according to the current legislation in Russia and Ukraine, which prohibits use of spy gadgets that can record video, audio or take photographs in an inconspicuous manner. Concerns were also raised in regard to the privacy and security of Google Glass users in the event that the device is stolen or lost, an issue that was raised by a US congressional committee. As part of its response to the governmental committee, Google stated in early July that is working on a locking system and raised awareness of the ability of users to remotely reset Google Glass from the web interface in the event of loss. Several facilities have banned the use of Google Glass before its release to the general public, citing concerns over potential privacy-violating capabilities. Other facilities, such as Las Vegas casinos, banned Google Glass, citing their desire to comply with Nevada state law and common gaming regulations which ban the use of recording devices near gambling areas.

Safety considerations

Concerns have also been raised on operating motor vehicles while wearing the device. On 31 July 2013 it was reported that driving while wearing Google Glass is likely to be banned in the UK, being deemed careless driving, therefore a fixed penalty offense, following a decision by the Department for Transport. In the U.S., West Virginia state representative Gary G. Howell introduced an amendment in March 2013 to the state's law against texting while driving that would include bans against "using a wearable computer with head mounted display." In an interview, Howell stated, "The primary thing is a safety concern, it [the glass headset] could project text or video into your field of vision. I think there's a lot of potential for distraction."

In October 2013, a driver in California was ticketed for "driving with monitor visible to driver (Google Glass)" after being pulled over for speeding by a San Diego Police Department officer. The driver was reportedly the first to be ticketed for driving while wearing a Google Glass. While the judge noted that 'Google Glass fell under "the purview and intent" of the ban on driving with a monitor', the case was thrown out of court due to lack of proof the device was on at the time.

Functionality considerations

Today most AR devices look bulky, and applications such as navigation, a real-time tourist guide, and recording, can drain smart glasses' batteries in about 1–4 hours. Battery life might be improved by using lower-power display systems (as with the Vaunt), wearing a battery pack elsewhere on the body (such as a belt pack or companion smart necklace).