Txhawm rau saib xyuas ib puag ncig thiab taug kev hauv ntiaj teb tiag tiag, tus neeg hlau yuav tsum muaj peev xwm tau txais cov duab thiab kev ntsuas ib puag ncig hauv qab cov teeb pom kev sib txawv. Nyob rau hauv xyoo tas los no, cov kws tshawb fawb thiab engineers thoob plaws ntiaj teb tau ua hauj lwm los tsim ntau thiab ntau dua sensors los koom ua ke rau hauv cov neeg hlau, cov tshuab soj ntsuam lossis lwm yam khoom siv uas tuaj yeem hnov lawv ib puag ncig.
Raws li Memes Consulting, cov kws tshawb fawb los ntawm Hong Kong Polytechnic University, Peking University, Yonsei University thiab Fudan University tsis ntev los no tau tsim ib hom tshiab ntawm bionic tsis pom kev sensor uas siv lub tshuab ua kom pom kev ua kom pom kev ua haujlwm ntawm lub hlwb thiab tuaj yeem siv ntau yam ntaub ntawv tau sau. nyob rau hauv lub teeb. Qhov no bionic tsis pom kev sensor yog raws li phototransistors ua los ntawm molybdenum disulfide.
Diam duab ntawm biomimetic vision sensor array (sab laug); schematic qauv ntawm lub zeem muag sensor chav tsev thiab optical microscope duab (txoj cai)
"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."
Xyoo 2018, Yang Chai thiab nws cov npoj yaig tau luam tawm thawj daim ntawv ntawm optoelectronic nco, uas lawv tau qhia txog kev hloov pauv lub cim xeeb uas tuaj yeem ua lub teeb pom kev thiab cov haujlwm logic. Ib xyoos tom qab, pab neeg no tau qhia txog hom tshiab ntawm photoresistive random nkag tau lub cim xeeb nrog peb txoj haujlwm sib txawv. Tshwj xeeb, cov cuab yeej tshiab tuaj yeem paub qhov chaw ib puag ncig, khaws cov ntaub ntawv hauv lub cim xeeb, thiab ua haujlwm neuromorphic pom kev ua ntej.
"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.
Lub xeev- ntawm-- cov duab kos duab sensors raws li CMOS thev naus laus zis feem ntau muaj qhov txwv tsis pub muaj ntau ntawm 70 dB. Txawm li cas los xij, qhov dynamic ntau yam no yog nqaim dua li cov teeb pom kev zoo ntawm cov xwm txheej ntuj (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.
Optoelectronic cov khoom siv nrog lub teeb- hloov kho lub zeem muag thiab kev paub dav dav ntawm cov khoom siv hluav taws xob tuaj yeem muaj txiaj ntsig zoo heev. Piv txwv li, lawv tuaj yeem pab txhim kho kev ua haujlwm ntawm cov cuab yeej pom kev hauv computer, txo qhov nyuaj ntawm cov khoom siv los tsim cov neeg hlau lossis lwm cov tshuab ntsuas, thiab txhim kho qhov tseeb ntawm cov duab paub txog cov tshuab.
Txawm li cas los xij, lwm pab pawg tshawb fawb tau tsim cov khoom siv optoelectronic uas tuaj yeem hloov kho rau cov teeb pom kev sib txawv yav dhau los. Txawm li cas los xij, feem ntau ntawm cov khoom siv yav dhau los pom tau tsuas yog ua raws li lub teeb hloov kho ntawm lub retina. Txoj kev hloov kho qhov tsaus ntuj tau dhau los ua pov thawj nyuaj dua rau simulate.
"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."
Artificial simulation ntawm photoreceptors thiab kab rov tav hlwb nyob rau hauv lub retina rau qhov muag adaptation (tsaus adaptation thiab lub teeb adaptation)
Lub zeem muag biomimetic tsim los ntawm Yang Chai thiab cov npoj yaig yog ua los ntawm phototransistors ua los ntawm cov khoom siv ultrathin semiconductor hu ua molybdenum disulfide. Cov phototransistors lawv tau siv muaj ntau lub suab ntxiab uas tuaj yeem ntxiab lossis tso cov hluav taws xob hauv cov channel ntawm qhov sib txawv ntawm qhov sib txawv.
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."
Yang Chai thiab nws cov npoj yaig tau soj ntsuam lub zeem muag bionic nyob rau hauv ntau qhov kev sim thiab pom tias nws tuaj yeem ua haujlwm zoo ntawm tib neeg retina, ua tiav cov txiaj ntsig zoo kawg nkaus hauv qhov tsaus ntuj thiab lub teeb hloov pauv. Tsis tas li ntawd, nws muaj qhov kev nkag siab ntau dua (199 dB) piv rau cov kev daws teeb meem yav dhau los.
"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."
Hauv kev tshawb fawb yav tom ntej, cov kws tshawb fawb npaj yuav txhim kho qhov ua tau zoo ntawm lub zeem muag sensor, thaum tseem siv nws los tsim cov tshuab loj - nplai uas muaj cov sensor arrays. Qhov zoo tshaj plaws, lawv xav tsim cov sensor array ntawm qhov hloov tau yooj yim lossis hemispherical substrate kom muaj kev pom dav dua.
"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."
GMKJ Technology tau koom nrog kev noj qab haus huv thiab ntse teeb pom kev zoo, muab ntau yam ntawm UVA UVB UVC LED, infrared IR LED VCSEL cov khoom lag luam thiab cov kev daws teeb meem rau kev lag luam. Nws muaj ntau pua tus neeg ua haujlwm siab -cov koom tes zoo hauv kev lag luam hauv tsev thiab txawv teb chaws los koom ua ke txhawb kev siv lub teeb pom kev zoo los tsim lub neej noj qab haus huv thiab ntse. .
