Er mwyn monitro'r amgylchedd a llywio'r byd go iawn, dylai'r robot allu caffael delweddau a mesuriadau amgylcheddol o dan amodau goleuo cefndir gwahanol. Yn ystod y blynyddoedd diwethaf, mae ymchwilwyr a pheirianwyr ledled y byd wedi bod yn gweithio i ddatblygu synwyryddion mwy a mwy datblygedig i integreiddio i robotiaid, systemau gwyliadwriaeth neu ddyfeisiau eraill a all synhwyro eu hamgylchedd.
Yn ôl Memes Consulting, mae ymchwilwyr o Brifysgol Polytechnig Hong Kong, Prifysgol Peking, Prifysgol Yonsei a Phrifysgol Fudan yn ddiweddar wedi datblygu math newydd o synhwyrydd gweledigaeth bionig sy'n defnyddio mecanwaith sy'n efelychu swyddogaeth retinol yn artiffisial a gellir ei ddefnyddio mewn amrywiaeth o ddata. dan amodau golau. Mae'r synhwyrydd gweledigaeth bionig hwn yn seiliedig ar ffototransistorau wedi'u gwneud o disulfide molybdenwm.
Llun o'r arae synhwyrydd gweledigaeth biomimetig (chwith); strwythur sgematig yr uned synhwyrydd gweledigaeth a delwedd microsgop optegol (dde)
"Our research team started work on optoelectronic memory five years ago," said Yang Chai, one of the researchers who developed the vision sensor. "This emerging device can output light-dependent and history-dependent signals, enabling image integration. , Weak signal accumulation, spectral analysis and other complex image processing functions, the multi-functional integration of sensing, data storage and data processing into one device."
Yn 2018, cyhoeddodd Yang Chai a'i gydweithwyr y papur cyntaf ar gof optoelectroneg, lle cyflwynwyd dyfais cof newid gwrthiannol a all berfformio gweithrediadau synhwyro golau a rhesymeg. Flwyddyn yn ddiweddarach, cyflwynodd y tîm fath newydd o gof mynediad ffotoresistig ar hap gyda thair swyddogaeth wahanol. Yn benodol, gall y ddyfais newydd synhwyro'r amgylchedd, storio'r wybodaeth yn y cof, a pherfformio gweithrediadau rhagbrosesu gweledol niwromorffig.
"We studied the concepts of near-sensor and in-sensor computing paradigms in 2020 and published our views in the field." Yang Chai continued, "This new research on biomimetic vision sensors builds on our On top of all previous efforts."
The intensity of ambient natural light varies widely, with a total range of 280 dB. When the human retina senses external light signals, it adjusts the light sensitivity of its photoreceptors (i.e., rods and cones) according to the strength of the signal. This ultimately enables the human eye to gradually adapt to varying levels of lighting, allowing it to see clearly in both dark and bright environments, an ability known as "visual adaptation."
"For example, when you enter a dark cinema from a bright hall, you can hardly see anything at first, but after a while in the cinema, it becomes easier to see things," explains Yang Chai. "This phenomenon is called scotopic adaptation. Conversely, if you go from a dark movie theater to a sunny outdoors, you'll feel very dazzled at first, and it takes a while to get used to seeing what's going on around you. The process The opposite of dark adaptation is called photopic adaptation."
The main goal of Yang Chai and his colleagues' recent work is to build a vision sensor inspired by the structure and function of the human retina. To do this, they first started by studying the human retina and then tried to design perceptual strategies that would allow them to artificially simulate visual adaptations.
Yn nodweddiadol, mae gan gyflwr{0}o'r-synwyryddion delwedd celf sy'n seiliedig ar dechnoleg CMOS ystod ddeinamig gyfyngedig o 70 dB. Fodd bynnag, mae'r ystod ddeinamig hon yn llawer culach na'r ystod goleuo o olygfeydd naturiol (280 dB).
"To achieve visual perception over a wide range of light intensities, researchers have explored the use of controlled optical apertures, liquid lenses, adjustable exposure times, and denoising algorithms in post-processing," said Yang Chai. "However, these Methods often require complex hardware and software resources."
Dark and light adaptation of biomimetic vision sensor arrays. (a) Schematic of the dark adaptation test: recognition of low-light images using an 8 x 8 pixel array in a dark environment. (b) Schematic diagram of light adaptation test: recognition of high-illuminance images using an 8 x 8 pixel array in a bright environment. (c) Dark adaptation process to identify the "8" pattern. (d) The photoadaptation process to identify the "8" pattern.
Gallai dyfeisiau optoelectroneg â-gweledigaeth addasol golau ac ystod synhwyro eang mewn terfynellau synhwyraidd fod â chymwysiadau gwerthfawr iawn. Er enghraifft, gallant helpu i wella perfformiad offer golwg cyfrifiadurol, lleihau'r cymhlethdod caledwedd sydd ei angen i adeiladu robotiaid neu systemau synhwyro eraill, a gwella cywirdeb systemau adnabod delweddau.
Er, mae timau ymchwil eraill wedi datblygu dyfeisiau optoelectroneg a all addasu i wahanol amodau goleuo yn y gorffennol. Fodd bynnag, ni all y rhan fwyaf o'r dyfeisiau a ddangoswyd yn flaenorol ond dynwared mecanwaith addasu golau y retina. Mae'r broses addasu tywyll wedi bod yn anoddach i'w hefelychu hyd yma.
"There is still a long way to go to fully replicate the visual adaptation function of the retina," explains Yang Chai. "To achieve this, we designed a phototransistor-based vision sensor using ultra-thin semiconductors that can The degree of dark adaptation and light adaptation in the same device was controlled by applying different gate voltages. In this way, we simulated photoreceptors and horizontal cells in the retina and successfully achieved a sensing range of 199 dB. Vision-adaptive devices in biomimetic sensors."
Efelychu artiffisial o ffotoreceptors a chelloedd llorweddol yn y retina ar gyfer addasu gweledol (addasu tywyll ac addasu golau)
Mae'r synhwyrydd gweledigaeth biomimetig a ddatblygwyd gan Yang Chai a chydweithwyr yn seiliedig ar ffototransistorau wedi'u gwneud o ddeunydd lled-ddargludyddion ultrathin o'r enw disulfide molybdenwm. Mae gan y ffototransistorau a ddefnyddiwyd ganddynt gyflyrau trap gwefr lluosog sy'n gallu trapio neu ryddhau electronau o fewn y sianel ar folteddau adwy gwahanol.
Ultimately, these states allow researchers to dynamically tune the conductance of their devices. This, in turn, allowed them to artificially simulate the dark- and light-adaptive mechanisms of the human retina, thereby expanding the range of their sensor's perception of different lighting conditions.
"Our bionic vision sensor has several advantages and features," said Yang Chai. "First, the visual adaptation function is implemented in a single device, which greatly reduces the footprint. Second, multiple functions can be implemented on a single device. , including light sensing, memory, and processing. Finally, dark and light adaptation under different light intensities can be achieved by controlling its gate voltage."
Gwerthusodd Yang Chai a'i gydweithwyr y synhwyrydd gweledigaeth bionig mewn cyfres o brofion a chanfod y gallai ddynwared swyddogaeth y retina dynol yn effeithiol, gan gyflawni canlyniadau rhyfeddol mewn addasiad tywyll a golau. At hynny, mae ganddo ystod canfyddiadol sylweddol uwch (199 dB) o gymharu ag atebion a gynigiwyd yn flaenorol.
"Our vision sensor can enrich machine vision functions, reduce hardware complexity, and achieve high image recognition efficiency," said Yang Chai, "All these advantages are available in areas such as autonomous driving, face recognition, and industrial manufacturing in complex lighting environments. great application prospects."
Mewn astudiaethau yn y dyfodol, mae'r ymchwilwyr yn bwriadu gwella perfformiad y synhwyrydd golwg ymhellach, tra hefyd yn ei ddefnyddio i wneud systemau ar raddfa fawr sy'n cynnwys araeau synhwyrydd. Yn ddelfrydol, maent am adeiladu'r arae synhwyrydd hwn ar swbstrad hyblyg neu hemisfferig i alluogi maes golygfa ehangach.
"One area that needs improvement is the adaptation time of our vision sensor, as it is still not enough to support machine vision applications." Yang Chai added, "Our goal is to reduce the adaptation time to the microsecond level. In addition, the vision sensor array scale Further improvements are also needed. Our near-term target for array size is greater than 100 x 100 pixels. Finally, the heterogeneous integration of vision sensors and post-processing units, including silicon-based control circuits, is a very important step toward practical applications."
Mae GMKJ Technology yn ymwneud yn ddwfn â ffynonellau golau iach a smart, gan ddarparu ystod lawn o gynhyrchion UVA UVB UVC LED, isgoch IR LED VCSEL ac atebion i'r farchnad. Mae ganddo gannoedd o bartneriaid o ansawdd uchel mewn marchnadoedd domestig a thramor i hyrwyddo'r defnydd o dechnoleg ysgafn ar y cyd i greu bywyd iach a deallus. .
