CN114295565A - Method, apparatus, device and medium for determining quantum efficiency of image sensor - Google Patents
Method, apparatus, device and medium for determining quantum efficiency of image sensor Download PDFInfo
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Abstract
The invention provides a method for measuring quantum efficiency of an image sensor, which comprises the following steps: the image sensor receives the continuous spectrum from the light source through the optical fiber panel; the image sensor respectively obtains an image at each interval unit integration time under the dark field and exposure conditions to obtain a dark field image group and an exposure image group; subtracting the pixel value of the exposure image group and the pixel value of the dark field image group to obtain a data difference value of unit integration time; acquiring an image of the continuous spectrum after being filtered by a plurality of specific wavelengths, and positioning a specific position of the specific wavelength in the continuous spectrum through an image sensor; fitting to obtain an optical power curve and an optical power value of a first wavelength through the specific position, the continuous spectrum and the corresponding relation between the specific position and the optical power; and calculating the quantum efficiency of the image sensor corresponding to the first wavelength according to the optical power value, the first wavelength, the pixel size, the unit integration time, the data difference value and the conversion gain.
Description
Technical Field
The present invention relates to the field of image sensor technology, and more particularly, to a method, apparatus, device, and medium for determining quantum efficiency of an image sensor.
Background
Quantum Efficiency (QE) is a parameter describing the ability of a pixel to convert photons into electrons and is also an important parameter in evaluating the performance of an image sensor. The higher the quantum efficiency, the stronger the photoelectric conversion capability of the image sensor at that wavelength, and the stronger the weak light representation capability. The accuracy of quantum efficiency lies in the wavelength range of the separated monochromatic light, the smaller the wavelength range is, namely, the higher the accuracy is, the more continuous the quantum efficiency curve is, the more accurate the result is.
At present, the main method for testing quantum efficiency is as follows: the uniform light output by the integrating sphere uses a halogen light source, has relatively continuous spectrum, and passes through the light with the required wavelength by switching different band-pass filters. The wavelength span is large, typically between 10nm and 20nm, due to the bandpass filtering used. The deviation of the quantum efficiency curve is large. Accordingly, there is a need for methods, devices, apparatuses, and media for determining quantum efficiency of image sensors to ameliorate the above-mentioned problems.
Disclosure of Invention
An object of the present invention is to provide a method, an apparatus, a device and a medium for measuring quantum efficiency of an image sensor, which are used for accurately measuring quantum efficiency of the image sensor.
In a first aspect, the present invention provides a method for determining quantum efficiency of an image sensor, comprising: the image sensor receives the continuous spectrum from the light source through the optical fiber panel; the image sensor respectively obtains one image at each interval unit integration time under the dark field and exposure conditions to obtain a dark field image group and an exposure image group; subtracting the pixel value of the exposure image group from the pixel value of the dark field image group to obtain a data difference value of the unit integration time; acquiring an image of the continuous spectrum after being filtered by a plurality of specific wavelengths, and positioning a specific position of the specific wavelength in the continuous spectrum through the image sensor; fitting to obtain an optical power curve according to the specific position, the continuous spectrum and the corresponding relation between the continuous spectrum and the optical power; acquiring an optical power value of a first wavelength through the optical power curve; and calculating the quantum efficiency of the image sensor corresponding to the first wavelength according to the optical power value, the first wavelength, the pixel size, the unit integration time, the data difference value and the conversion gain.
The method for measuring the quantum efficiency of the image sensor has the advantages that the quantum efficiency of any first wavelength can be obtained only by limited dark field image groups and exposure image groups, the quantum efficiency of the image sensor under each wavelength can be comprehensively and continuously shown, the test flow is simplified, and the test efficiency is improved.
Optionally, the quantum efficiency QE of the first wavelength satisfies the following formula:
QE＝μe/μp
wherein, mueIs the average number of photoelectrons generated in unit integration time at the first wavelength; mu.spThe number of incident photons generated in unit integration time at the first wavelength; the average number of photoelectrons satisfies the following formula:
μe＝Δμ/CG
wherein Δ μ is a data difference value of the unit integration time; CG is the conversion gain. The method has the advantage that the quantum efficiency of the first wavelength is calculated through the average number of photoelectrons and the average number of photoelectrons.
Optionally, the method for calculating the conversion gain includes: keeping the light source unchanged, and adjusting the exposure time of the image sensor; calculating the time domain variance and the average gray value of the pixel value of the region of interest under each exposure time; drawing a curve graph by taking the average gray value as a horizontal axis and the time domain variance as a vertical axis; and calculating the slope of a linear section of the graph, namely the conversion gain. The method has the advantage that the conversion gain is calculated by changing the image obtained by the exposure time.
Optionally, the number of incident photons satisfies the following formula:
μp＝50.34·A·texp·λ·E
wherein E is the optical power value, λ is the wavelength, A is the pixel size, texpIs the unit integration time. The method has the advantages that the number of incident photons is calculated through the light power value, the wavelength, the pixel size and the unit integration time.
Optionally, subtracting the pixel value of the exposure image group and the pixel value of the dark field image group to obtain a data difference value of unit integration time, including: the image sensor is under dark field condition, and the unit integration time t is arranged at intervalsexpObtaining a dark field image to obtain a dark field image group; the image sensor is arranged at intervals of the unit integration time t under the exposure conditionexpAcquiring an exposure image to obtain an exposure image group; the dark-field image group at least comprises a first dark-field image and a second dark-field image; the exposure image group at least comprises a first exposure image and a second exposure image; the pixel value is subtracted to obtain the unit integration time texpSatisfies the following equation:
Δμ＝(IMG2-IMG_dark2)-(IMG1-IMG_dark1)
wherein IMG1 is a pixel value of a first exposure image, the IMG2 is a pixel value of a second exposure image, the IMG _ dark1 is a pixel value of a first dark field image, the IMG _ dark2 is a pixel value of a second dark field image; the acquisition time intervals of the first exposure/dark field image and the second exposure/dark field image are unit integration time texp. The method has the advantages that the data difference value is calculated through the pixel values of the first dark field image and the second dark field image.
Optionally, the method further includes: acquiring a band-pass spectrum, wherein the band-pass spectrum is generated by a continuous spectrum emitted by the light source through a dispersion mechanism and an optical filter; and the rows or columns of the photosensitive units of the image sensor are parallel to the spectral lines of the continuous spectrum. The method has the advantages that the rows or the columns of the photosensitive units of the image sensor are parallel to the spectral lines of the continuous spectrum, so that the received wavelengths of the photosensitive units of the image sensor in each row or each column are the same, and error interference is reduced during averaging.
In a second aspect, the present invention provides an apparatus for determining quantum efficiency of an image sensor, for use in the method of any one of the first aspects, the apparatus comprising: the device comprises a photosensitive unit, a light source, a dispersion mechanism, a light filter, a processing unit and an optical fiber panel; the light source is used for providing light rays; the dispersion mechanism is used for separating the light with different wavelengths in the light source to obtain a continuous spectrum; the light sensing unit is used for receiving the continuous spectrum from the light source through the optical fiber panel; the image sensor respectively obtains one image at each interval unit integration time under the dark field and exposure conditions to obtain a dark field image group and an exposure image group; the processing unit is used for subtracting the pixel value of the exposure image group from the pixel value of the dark field image group to obtain a data difference value of the unit integration time; the optical filter is arranged between the light source and the optical fiber panel and used for filtering a specific wavelength, and a specific position of the specific wavelength in the continuous spectrum is positioned through the image sensor; the processing unit is further used for fitting to obtain the optical power curve through the specific position, the continuous spectrum and the corresponding relation between the continuous spectrum and the optical power; acquiring an optical power value of a first wavelength through the optical power curve; and calculating the quantum efficiency of the image sensor corresponding to the first wavelength according to the optical power value, the first wavelength, the pixel size, the unit integration time, the data difference value and the conversion gain.
Optionally, the device further comprises an adjustment mechanism; the adjusting mechanism is used for adjusting the angle of the optical filter, so that the line or the column of the photosensitive unit of the image sensor is parallel to the spectral line of the continuous spectrum. The continuous spectrum generation device has the advantages that when light emitted by the light source passes through the dispersion mechanism, the continuous spectrum is generated; by selecting spectral lines representing different wavelengths from the continuous spectrum as the first wavelength to perform quantum efficiency analysis, the time for acquiring the first wavelength image is saved; the pixel value of the whole image does not need to be processed, redundant data are reduced, and efficient determination is facilitated.
Optionally, a baffle is disposed between the light source and the dispersion mechanism, a slit is disposed in the baffle, and the slit is used for making light penetrating through the baffle be in a strip shape. The light source has the advantages that the light penetrating through the baffle is in a strip shape through the slit, so that a parallel light source with good coherence is obtained, and interference is reduced.
Optionally, the device further comprises a luminescent material layer disposed on the optical fiber panel; and the photosensitive unit is used for absorbing invisible light, converting the invisible light into visible light and transmitting the visible light to the image sensor. The image sensor has the beneficial effects that the luminescent material layer receives invisible light and emits the visible light to the photosensitive unit of the image sensor, so that the quantum efficiency of the image sensor at the wavelength of the invisible light can be calculated conveniently.
Drawings
FIG. 1 is a schematic flow chart of a method for determining quantum efficiency of an image sensor according to the present invention;
FIG. 2 is a schematic diagram of the distribution of continuous spectra in a pixel unit according to the present invention;
fig. 3 (a) is a graph of optical power of the light source provided by the present invention;
fig. 3 (b) is a graph of optical power at a specific wavelength according to the present invention;
FIG. 4 is a graph illustrating the mean gray value and the time domain variance provided by the present invention;
FIG. 5 is a schematic structural diagram of an apparatus for measuring quantum efficiency of an image sensor according to the present invention;
fig. 6 is a schematic view of an installation structure of the fiber optic faceplate provided by the present invention.
Reference numbers in the figures:
100. a device; 101. a light source; 102. a fiber optic faceplate; 103. a light sensing unit; 104. a processing unit; 105. a storage unit; 106. a baffle plate; 107. a dispersion mechanism; 108. an optical filter; 109. an adjustment mechanism; 310. a layer of light emitting material.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings of the present invention, and it is obvious that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention. Unless defined otherwise, technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention belongs. As used herein, the word "comprising" and similar words are intended to mean that the element or item listed before the word covers the element or item listed after the word and its equivalents, but does not exclude other elements or items.
Fig. 1 is a schematic flow chart of a method for measuring quantum efficiency of an image sensor according to the present invention.
Aiming at the problems in the prior art, the invention provides a method for measuring the quantum efficiency of an image sensor, which comprises the following steps:
s101, an image sensor receives continuous spectrum from a light source through an optical fiber panel;
fig. 2 is a schematic diagram of the distribution of the continuous spectrum in the pixel unit according to the present invention.
In some embodiments, as shown in FIG. 2, a continuous spectrum of wavelengths from 350nm to 750nm is projected onto the light-sensing elements of the image sensor.
S102, the image sensor respectively obtains an image at intervals of unit integration time under dark field and exposure conditions to obtain a dark field image group and an exposure image group;
s103, subtracting the pixel value of the exposure image group and the pixel value of the dark field image group by the image sensor to obtain a data difference value of the unit integration time;
it is worth to be noted that the data difference value can be executed by FPGA \ DSP \ upper computer software and the like.
In some embodiments, subtracting the pixel values of the exposure image group and the pixel values of the dark field image group to obtain a data difference value per integration time comprises:
the image sensor 203 is under dark field condition with unit integration time t at intervalsexpObtaining a dark field image to obtain a dark field image group; the image sensor 203 is under exposure conditions at intervals of the unit integration time texpAcquiring an exposure image to obtain an exposure image group;
the dark-field image group at least comprises a first dark-field image and a second dark-field image; the exposure image group at least comprises a first exposure image and a second exposure image; the pixel value is subtracted to obtain the unit integration time texpSatisfies the following equation:
Δμ＝(IMG2-IMG_dark2)-(IMG1-IMG_dark1)
wherein IMG1 is a pixel value of a first exposure image, the IMG2 is a pixel value of a second exposure image, the IMG _ dark1 is a pixel value of a first dark field image, the IMG _ dark2 is a pixel value of a second dark field image; the acquisition time intervals of the first exposure/dark field image and the second exposure/dark field image are unit integration time texp。
In some embodiments, the difference Δ μ 1 satisfies the following equation:
Δμ1＝(IMG2-IMG_dark2)-(IMG1-IMG_dark1)
the difference Δ μ 2 satisfies the following equation:
Δμ2＝(IMG3-IMG_dark3)-(IMG2-IMG_dark2)
wherein IMG1 is a pixel value of a first exposure image, the IMG2 is a pixel value of a second exposure image, and the IMG3 is a pixel value of a third exposure image; the IMG dark1 is a pixel value of a first dark field image, the IMG dark2 is a pixel value of a second dark field image, and the IMG dark3 is a pixel value of a third dark field image; the acquisition time intervals of the first exposure/dark field image, the second exposure/dark field image and the third exposure/dark field image are unit integration time texp. The difference value delta mu is obtained by averaging the difference value delta mu 1 and the difference value delta mu 2, which is beneficial to reducing errors. Or by comparing the difference Δ μ 1 with the difference Δ μ 2 to facilitate analysis of the effect of noise on the data difference.
In other embodiments, the number of images in the exposure image group and the dark field image group can be any integer greater than or equal to two.
S104, obtaining the filtered image of the continuous spectrum, and positioning the image sensor to specific positions of a plurality of specific wavelengths in the continuous spectrum;
s105, fitting to obtain a light power curve according to the specific position, the continuous spectrum and the corresponding relation between the continuous spectrum and the light power; acquiring an optical power value of a first wavelength through the optical power curve;
fig. 3 (a) shows an optical power curve of the light source 101 provided by the present invention; fig. 3 (b) is a graph of optical power at a specific wavelength according to the present invention.
In some embodiments, the optical power curve of the known light source 101 is shown as (a) in fig. 3. As shown in fig. 3 (b), wavelengths of 450nm, 550nm and 650nm are selected as specific wavelengths, and the specific positions of the wavelengths of 450nm, 550nm and 650nm in the continuous spectrum are located as 16 rows, 35 rows and 52 rows, respectively.
In other embodiments, the specific wavelength may be any wavelength in the continuous spectrum. The specific location may be any location in the continuous spectrum.
In some embodiments, the optical power curve is obtained by a nonlinear regression fitting method through specific positions of the wavelengths of 450nm, 550nm and 650nm in the continuous spectrum and the known optical power curve of the light source 101. And acquiring an optical power value with the first wavelength of 500nm through the optical power curve.
In other embodiments, the first wavelength may be any wavelength in the continuous spectrum. The optical power curve may also be obtained by other fitting methods.
And S106, calculating the quantum efficiency of the image sensor at the first wavelength according to the optical power value, the first wavelength, the pixel size, the unit integration time, the data difference value and the conversion gain.
In some embodiments, the quantum efficiency QE of the first wavelength satisfies the following equation:
QE＝μe/μp
wherein, mueIs the average number of photoelectrons generated in unit integration time at the first wavelength; mu.spThe number of incident photons generated in unit integration time at the first wavelength;
the average number of photoelectrons satisfies the following formula:
μe＝Δμ/CG
wherein Δ μ is a data difference value of the unit integration time; CG is the conversion gain.
It is worth mentioning that, in some embodiments, the method for calculating the conversion gain includes: keeping the light source 101 unchanged, and adjusting the exposure time of the image sensor 203; calculating the time domain variance and the average gray value of the pixel value of the region of interest under each exposure time; drawing a curve graph by taking the average gray value as a horizontal axis and the time domain variance as a vertical axis; and calculating the slope of a linear section of the graph, namely the conversion gain.
In some embodiments, the exposure time of the image sensor 203 is the unit integration time texp(ii) a The region of interest is the entire area of the exposure/dark field image.
In other embodiments, the region of interest is a partial region of an exposure/dark field image.
FIG. 4 is a graph illustrating the mean gray value and the time domain variance provided by the present invention.
In some embodiments, a graph is drawn with the mean gray value as the horizontal axis and the time domain variance as the vertical axis; as shown in fig. 4, the slope of the graph when the average gray-scale value is less than 600 is calculated, i.e. the conversion gain.
In some embodiments, the number of incident photons satisfies the following equation:
μp＝50.34·A·texp·λ·E
wherein E is the optical power value, λ is the wavelength, A is the pixel size, texpIs the unit integration time.
It is worth noting that in some specific embodiments, the pixel size is the size of the photosensitive unit. The unit integration time is the acquisition time interval of the first exposure/dark field image and the second exposure/dark field image.
In some embodiments, the method further comprises: acquiring a band-pass spectrum, wherein the band-pass spectrum is generated by a continuous spectrum emitted by the light source 101 through a dispersion mechanism 107 and an optical filter 108; the rows or columns of the light sensing units 103 of the image sensor 203 are parallel to the spectral lines of the continuous spectrum.
It is worth mentioning that the rows or columns of the light sensing units 103 of the image sensor 203 are parallel to the spectral lines of the continuum, and thus the extension direction of the band-pass spectrum is parallel to the rows or columns of the light sensing units 103 of the image sensor 203.
Fig. 5 is a schematic structural diagram of an apparatus for measuring quantum efficiency of an image sensor according to the present invention.
The present invention also provides an apparatus 100 for determining quantum efficiency of an image sensor, as shown in fig. 5, for use in the method of any one of claims 1 to 6, the apparatus 100 comprising: a light receiving unit 103, a light source 101, a dispersion mechanism 107, a filter 108, a processing unit 104, and an optical fiber panel 102. The light source 101 is used for providing light. The dispersion mechanism 107 is configured to separate light with different wavelengths in the light source 101 to obtain a continuous spectrum. The light sensing unit 103 is used for receiving the continuous spectrum from the light source 101 through the optical fiber panel 102. The image sensor 203 respectively obtains an image at each interval unit integration time under the dark field and exposure conditions to obtain a dark field image group and an exposure image group. The processing unit 104 is configured to subtract the pixel value of the exposure image group from the pixel value of the dark field image group to obtain a data difference value of the unit integration time. The optical filter 108 is inserted between the light source 101 and the fiber optic faceplate 102, and is positioned at a specific position where a plurality of specific wavelengths are in the continuous spectrum. The processing unit 104 is further configured to fit the optical power curve including the optical power value of the first wavelength to the specific position and the known optical power curve of the light source 101. And calculating the quantum efficiency of the image sensor 203 at the first wavelength according to the optical power value, the first wavelength, the pixel size, the unit integration time, the data difference value and the conversion gain.
It should be understood that the Processing Unit may be a Central Processing Unit (CPU) or a Graphics Processing Unit (GPU), and the Processor may be other general purpose processors, Digital Signal Processors (DSPs), Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like. The various methods, steps and logic blocks disclosed in the embodiments of the present invention may be implemented or performed. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like. The steps of the method disclosed in connection with the embodiments of the present invention may be directly implemented by a hardware decoding processor, or implemented by a combination of hardware and software in the decoding processor.
Fig. 6 is a schematic view of an installation structure of the fiber optic faceplate provided by the present invention.
In some embodiments, as shown in fig. 6, the fiber optic faceplate 102 is fixedly mounted on the photosensitive unit 103 of the fiber optic faceplate 102. The fiber optic faceplate 102 is comprised of an array of optical fibers. The photosensitive units 103 are connected with the optical fibers in a one-to-one correspondence manner.
In other embodiments, the fiber optic panel 102 and the light sensing unit 103 of the fiber optic panel 102 may be detachably connected or may be connected in any other way. One of the light sensing units 103 may be connected to a plurality of the optical fibers, or one of the optical fibers may be connected to a plurality of the light sensing units 103.
In some embodiments, the dispersion mechanism 107 may be provided as a prism or other dispersion mechanism 107. The filter 108 may be configured as a bandpass filter 108 or other filter 108. The light source 101 may be provided as a composite light source or other light source.
In some embodiments, the device 100 further comprises an adjustment mechanism 109; the adjusting mechanism 109 is configured to adjust an angle of the optical filter 108 so that a row or a column of the light sensing unit 103 of the image sensor 203 is parallel to a spectral line of the continuous spectrum.
In some embodiments, a baffle 106 is disposed between the light source 101 and the dispersion mechanism 107, and a slit is disposed in the baffle 106, and the slit is used for making the light transmitted through the baffle 106 in a strip shape.
In some embodiments, the baffle 106 can be provided in two pieces, the two baffles 106 are arranged in parallel, and the light emitted from the light source 101 exits through the slit between the two baffles 106.
In other embodiments, the baffle 106 may be configured as a grating or other optical device, such that light transmitted through the optical device is in the form of a stripe.
In some embodiments, the apparatus 100 further includes a luminescent material layer 110 disposed on the fiber optic faceplate 102 for absorbing invisible light, converting the invisible light into visible light, and transmitting the visible light to the photosensitive unit 103 of the image sensor 203.
It is worth mentioning that silicon-based materials cannot absorb: ultraviolet (UV), Deep Ultraviolet (DUV), Extreme Ultraviolet (EUV), and roentgen rays (X-ray), which may damage silicon-based materials. The light is absorbed by the luminescent material, converted into visible light, and then subjected to light sensing by the image sensor.
In some embodiments, the luminescent material layer 110 is made of a scintillator for absorbing ultraviolet rays and emitting visible light to the photosensitive cells 103 of the image sensor 203. The quantum efficiency of the photosensitive unit 103 of the image sensor 203 in the ultraviolet band can be acquired, and damage to the photosensitive unit 103 caused by direct ultraviolet radiation is avoided.
In other embodiments, the light emitting material layer 110 may also be made of other light emitting materials.
Although the embodiments of the present invention have been described in detail hereinabove, it is apparent to those skilled in the art that various modifications and variations can be made to these embodiments. However, it is to be understood that such modifications and variations are within the scope and spirit of the present invention as set forth in the following claims. Moreover, the invention as described herein is capable of other embodiments and of being practiced or of being carried out in various ways.
Claims (10)
1. A method of determining quantum efficiency of an image sensor, comprising:
the image sensor receives the continuous spectrum from the light source through the optical fiber panel;
the image sensor respectively obtains one image at each interval unit integration time under the dark field and exposure conditions to obtain a dark field image group and an exposure image group;
subtracting the pixel value of the exposure image group from the pixel value of the dark field image group to obtain a data difference value of the unit integration time;
acquiring an image of the continuous spectrum after being filtered by a plurality of specific wavelengths, and positioning a specific position of the specific wavelength in the continuous spectrum through the image sensor;
fitting to obtain an optical power curve according to the specific position, the continuous spectrum and the corresponding relation between the continuous spectrum and the optical power; acquiring an optical power value of a first wavelength through the optical power curve;
and calculating the quantum efficiency of the image sensor corresponding to the first wavelength according to the optical power value, the first wavelength, the pixel size, the unit integration time, the data difference value and the conversion gain.
2. The method of claim 1, wherein the quantum efficiency QE for the first wavelength satisfies the following equation:
QE＝μe/μp
wherein, mueIs the average number of photoelectrons generated in unit integration time at the first wavelength；μpThe number of incident photons generated in unit integration time at the first wavelength;
the average number of photoelectrons satisfies the following formula:
μe＝Δμ/CG
wherein Δ μ is a data difference value of the unit integration time; CG is the conversion gain.
3. The method of claim 2, wherein the conversion gain is calculated by: keeping the light source unchanged, and adjusting the exposure time of the image sensor; calculating the time domain variance and the average gray value of the pixel value of the region of interest under each exposure time; drawing a curve graph by taking the average gray value as a horizontal axis and the time domain variance as a vertical axis; and calculating the slope of a linear section of the graph, namely the conversion gain.
4. The method of claim 2,
the incident photon number satisfies the following formula:
μp＝50.34·A·texp·λ·E
wherein E is the optical power value, λ is the wavelength, A is the pixel size, texpIs the unit integration time.
5. The method of claim 1, wherein subtracting the pixel values of the exposure image set from the pixel values of the dark field image set to obtain a data difference value per integration time comprises:
the image sensor is under dark field condition, and the unit integration time t is arranged at intervalsexpObtaining a dark field image to obtain a dark field image group; the image sensor is arranged at intervals of the unit integration time t under the exposure conditionexpAcquiring an exposure image to obtain an exposure image group;
the dark-field image group at least comprises a first dark-field image and a second dark-field image; the exposure image group at least comprises a first exposure image and a second exposure imageExposing an image; the pixel value is subtracted to obtain the unit integration time texpSatisfies the following equation:
Δμ＝(IMG2-IMG_dark2)-(IMG1-IMG_dark1)
wherein IMG1 is a pixel value of a first exposure image, the IMG2 is a pixel value of a second exposure image, the IMG _ dark1 is a pixel value of a first dark field image, the IMG _ dark2 is a pixel value of a second dark field image; the acquisition time intervals of the first exposure/dark field image and the second exposure/dark field image are unit integration time texp。
6. The method of claim 1, further comprising:
acquiring a band-pass spectrum, wherein the band-pass spectrum is generated by a continuous spectrum of the light source through a dispersion mechanism and an optical filter; and the rows or columns of the photosensitive units of the image sensor are parallel to the spectral lines of the continuous spectrum.
7. An apparatus for determining quantum efficiency of an image sensor, for use in the method of any one of claims 1 to 6, the apparatus comprising: the device comprises a photosensitive unit, a light source, a dispersion mechanism, a light filter, a processing unit and an optical fiber panel;
the light source is used for providing light rays;
the dispersion mechanism is used for separating the light with different wavelengths in the light source to obtain a continuous spectrum;
the light sensing unit is used for receiving the continuous spectrum from the light source through the optical fiber panel;
the image sensor respectively obtains one image at each interval unit integration time under the dark field and exposure conditions to obtain a dark field image group and an exposure image group;
the processing unit is used for subtracting the pixel value of the exposure image group from the pixel value of the dark field image group to obtain a data difference value of the unit integration time;
the optical filter is arranged between the light source and the optical fiber panel and used for filtering a specific wavelength, and a specific position of the specific wavelength in the continuous spectrum is positioned through the image sensor;
the processing unit is further used for fitting to obtain the optical power curve through the specific position, the continuous spectrum and the corresponding relation between the continuous spectrum and the optical power; acquiring an optical power value of a first wavelength through the optical power curve; and calculating the quantum efficiency of the image sensor corresponding to the first wavelength according to the optical power value, the first wavelength, the pixel size, the unit integration time, the data difference value and the conversion gain.
8. The device of claim 7, further comprising an adjustment mechanism;
the adjusting mechanism is used for adjusting the angle of the optical filter, so that the line or the column of the photosensitive unit of the image sensor is parallel to the spectral line of the continuous spectrum.
9. The apparatus according to claim 7, wherein a baffle is disposed between the light source and the dispersion mechanism, and a slit is disposed in the baffle for making the light penetrating the baffle in a strip shape.
10. The device of claim 7, further comprising a luminescent material layer disposed on the fiber optic faceplate for absorbing invisible light, converting the absorbed invisible light into visible light, and transmitting the visible light to the photosensitive unit of the image sensor.
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Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001137175A (en) * | 1999-11-18 | 2001-05-22 | Fuji Photo Film Co Ltd | Fluorescence image acquisition method and equipment |
| CN102012310A (en) * | 2009-09-08 | 2011-04-13 | 上海光谱仪器有限公司 | Novel full-band CCD detector performance evaluating system and method |
| US20130271628A1 (en) * | 2012-04-17 | 2013-10-17 | Skybox Imaging, Inc. | Sensor dark pixel offset estimation |
| US20160109381A1 (en) * | 2014-10-15 | 2016-04-21 | Sri Rama Prasanna Pavani | Multiple angle computational wafer inspection |
| CN105571834A (en) * | 2015-12-24 | 2016-05-11 | 中国电子科技集团公司第四十一研究所 | Measuring device of quantum efficiency of CCD device |
| JP2017005693A (en) * | 2015-06-08 | 2017-01-05 | 株式会社半導体エネルギー研究所 | Imaging apparatus and operation method therefor, and electronic apparatus |
| CN106840613A (en) * | 2017-02-14 | 2017-06-13 | 中国科学院新疆理化技术研究所 | The method of testing of complementary metal oxide semiconductors (CMOS) photon transfer curve and conversion gain after irradiation |
| CN110996095A (en) * | 2019-12-03 | 2020-04-10 | 哈尔滨工程大学 | Multiplication CCD multiplication gain fitting measurement method |
| CN113412613A (en) * | 2019-02-07 | 2021-09-17 | 纳米电子成像有限公司 | Fluorescence microscopy system, apparatus and method |
-
2021
- 2021-12-28 CN CN202111629837.9A patent/CN114295565B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001137175A (en) * | 1999-11-18 | 2001-05-22 | Fuji Photo Film Co Ltd | Fluorescence image acquisition method and equipment |
| CN102012310A (en) * | 2009-09-08 | 2011-04-13 | 上海光谱仪器有限公司 | Novel full-band CCD detector performance evaluating system and method |
| US20130271628A1 (en) * | 2012-04-17 | 2013-10-17 | Skybox Imaging, Inc. | Sensor dark pixel offset estimation |
| US20160109381A1 (en) * | 2014-10-15 | 2016-04-21 | Sri Rama Prasanna Pavani | Multiple angle computational wafer inspection |
| JP2017005693A (en) * | 2015-06-08 | 2017-01-05 | 株式会社半導体エネルギー研究所 | Imaging apparatus and operation method therefor, and electronic apparatus |
| CN105571834A (en) * | 2015-12-24 | 2016-05-11 | 中国电子科技集团公司第四十一研究所 | Measuring device of quantum efficiency of CCD device |
| CN106840613A (en) * | 2017-02-14 | 2017-06-13 | 中国科学院新疆理化技术研究所 | The method of testing of complementary metal oxide semiconductors (CMOS) photon transfer curve and conversion gain after irradiation |
| CN113412613A (en) * | 2019-02-07 | 2021-09-17 | 纳米电子成像有限公司 | Fluorescence microscopy system, apparatus and method |
| CN110996095A (en) * | 2019-12-03 | 2020-04-10 | 哈尔滨工程大学 | Multiplication CCD multiplication gain fitting measurement method |
Non-Patent Citations (1)
| Title |
|---|
| 姚萍萍等: "多角度偏振成像仪面阵探测器筛选及测试方法", 光学学报, vol. 40, no. 11, pages 1112002 * |
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