CN114157793B - System and method for coupling optical fiber image sensing element with photosensitive surface of image sensor - Google Patents

System and method for coupling optical fiber image sensing element with photosensitive surface of image sensor Download PDF

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Publication number
CN114157793B
CN114157793B CN202111499576.3A CN202111499576A CN114157793B CN 114157793 B CN114157793 B CN 114157793B CN 202111499576 A CN202111499576 A CN 202111499576A CN 114157793 B CN114157793 B CN 114157793B
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coupling
optical fiber
image sensor
photosensitive surface
light source
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CN114157793A (en
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黄永刚
焦朋
赵冉
王云
付杨
周游
王久旺
独雅婕
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China Building Materials Academy CBMA
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China Building Materials Academy CBMA
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N23/00—Cameras or camera modules comprising electronic image sensors; Control thereof
    • H04N23/50—Constructional details
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D21/00—Measuring or testing not otherwise provided for
    • G01D21/02—Measuring two or more variables by means not covered by a single other subclass
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N23/00—Cameras or camera modules comprising electronic image sensors; Control thereof
    • H04N23/50—Constructional details
    • H04N23/55—Optical parts specially adapted for electronic image sensors; Mounting thereof
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N23/00—Cameras or camera modules comprising electronic image sensors; Control thereof
    • H04N23/56—Cameras or camera modules comprising electronic image sensors; Control thereof provided with illuminating means
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N23/00—Cameras or camera modules comprising electronic image sensors; Control thereof
    • H04N23/60—Control of cameras or camera modules
    • H04N23/695—Control of camera direction for changing a field of view, e.g. pan, tilt or based on tracking of objects
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N25/00—Circuitry of solid-state image sensors [SSIS]; Control thereof
    • H04N25/70—SSIS architectures; Circuits associated therewith
    • H04N25/71—Charge-coupled device [CCD] sensors; Charge-transfer registers specially adapted for CCD sensors
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N25/00—Circuitry of solid-state image sensors [SSIS]; Control thereof
    • H04N25/70—SSIS architectures; Circuits associated therewith
    • H04N25/76—Addressed sensors, e.g. MOS or CMOS sensors

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  • Engineering & Computer Science (AREA)
  • Multimedia (AREA)
  • Signal Processing (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optical Couplings Of Light Guides (AREA)

Abstract

The invention relates to a system and a method for coupling an optical fiber image sensing element with a photosensitive surface in an image sensor. The system comprises: the main body structure unit comprises a light shield, a left bracket, a right bracket and a base, wherein the left bracket, the right bracket and the base are arranged in the light shield; the displacement positioning unit comprises a CMOS camera, a 360-degree rotary platform and an X/Y displacement platform; the positioning heating unit comprises a temperature control meter, a heating device and a vacuum adsorption device which are arranged outside the main body structure unit; the optical fiber transmission element clamping unit comprises an air-driven self-centering clamping device, a resolution/shearing standard template and a coupling interface pressure sensor; the monitoring display unit comprises a computer and a data line; the light source unit comprises an LED white light source, an ultraviolet light source and a light source controller. The system and the method provided by the invention not only can realize the rapid optical curing coupling of the optical fiber image sensing element and the photosensitive surface in the image sensor, but also can evaluate the coupling effect in real time by detecting indexes such as coupling resolution, relative transmittance and the like.

Description

System and method for coupling optical fiber image sensing element with photosensitive surface of image sensor
Technical Field
The invention belongs to the field of low-light night vision and particle detection imaging, and particularly relates to a system and a method for coupling an optical fiber image sensing element with a photosensitive surface in an image sensor.
Background
The optical fiber image transmission material mainly comprises hard optical fiber products such as optical fiber cones, optical fiber panels, optical fiber image inversors and the like. The material is a main window element in devices such as low-light night vision, particle detection and the like, and is also a key coupling medium element in ICCD or ICMOS image enhancement type sensing devices. The device is widely used in low-light night vision devices, framing/stripe cameras, ultraviolet/high-energy rays/single photon detection and other devices. In order to digitize the detected and identified image, the surface image formed by the optical fiber image transmission element is required to be digitally converted, so as to obtain an electronic image, further realize remote transmission, processing and storage of the image, and further introduce an image calculation method to further optimize the imaging quality and improve the signal to noise ratio. At present, the optical fiber image transmission element is well applied as a coupling medium between an image intensifier and CMOS or CCD in an ICCD, ICMOS and other image-enhanced cameras, and the application field is expanded from the traditional low-light night vision and particle detection devices to high-energy ray detection, single photon detection and other devices. The new field puts higher demands on imaging resolution and contrast, detection dynamic range, high sensitivity of the image intensifier camera, while the coupling of the image intensifier and the image sensor directly affects the coupling imaging quality, thus putting more demands on the coupling.
At present, there is no unified method and device for coupling an image enhancement member with a CCD or CMOS camera, the coupling adopts a method of combining mechanical or manual movement and microscopic observation, the coupling precision is not high, before coupling and curing, an optical fiber image transmission element is not easy to fix with the CCD or CMOS camera and is easy to generate micro-displacement, in addition, the stress of a coupling interface is not easy to control, and when the stress of a photosensitive surface is too large, even the damage of the photosensitive surface of a chip can be caused. And most importantly, the coupling effect is difficult to monitor in the coupling process, so that the coupling has certain random uncontrollability, the coupling qualification rate is low, and the coupling cost is high. Another difficulty with coupling is how to remove the glass cover without damaging the photosurface. The chip of the image sensor such as CCD/CMOS camera generally has a layer of protective glass cover plate to avoid the pollution or physical damage of the photosensitive surface on the core light, and the chip can be directly coupled with the optical fiber image transmission element only after the cover plate is taken down. Currently, these two processes are performed separately. If the two processes are brought together, the coupling time can be shortened while avoiding contamination of the photosurface.
Disclosure of Invention
In view of the above, the main objective of the present invention is to provide a system and a method for coupling an optical fiber image sensor with a photosensitive surface in an image sensor, which have the functions of rapid curing coupling, real-time monitoring and detecting of coupling effect, high-precision coupling, and removing a glass cover plate on the photosensitive surface.
The aim and the technical problems of the invention are realized by adopting the following technical proposal. The invention provides a system for coupling an optical fiber image sensing element with a photosensitive surface in an image sensor, which comprises the following components:
the main body structure unit comprises a light shield, a left bracket, a right bracket and a base, wherein the left bracket, the right bracket and the base are arranged in the light shield; the left bracket and the right bracket are respectively fixed on the base;
the displacement positioning unit comprises a CMOS camera, a 360-degree rotary platform and an X/Y displacement platform; the CMOS camera is arranged on the right bracket, the 360-degree rotating platform is arranged on the X/Y displacement platform, and the X/Y displacement platform is fixed on the base;
the positioning heating unit comprises a temperature control meter, a heating device and a vacuum adsorption device which are arranged outside the main body structure unit;
the optical fiber transmission element clamping unit comprises an air drive clamping device, a resolution/shearing standard template and a pressure sensor;
the monitoring display unit comprises a computer and a data line, wherein the computer is connected with an image sensor to be coupled; and
the light source unit comprises an LED white light source, an ultraviolet light source and a light source controller; the LED white light source is arranged on the right bracket, the ultraviolet light source is arranged on the left bracket, and the light source controller is arranged outside the main body structure unit.
Further, in the system for coupling the optical fiber image sensing element with the photosensitive surface in the image sensor, the X/Y displacement platform comprises two metal frames which are arranged up and down separately, two groups of positioning grating rulers, two groups of stepping motors and two groups of precise screws; the metal frame arranged below the base is arranged on the base, and two triangular grooves are formed in the metal frame; two triangular protrusions corresponding to the two triangular grooves are formed on the metal frame, and when the two triangular grooves are in contact with the two triangular protrusions, a micro-gap smaller than 1mm is formed.
Further, in the system for coupling the optical fiber image sensing element with the photosensitive surface in the image sensor, the optical fiber image sensing element is fixed on the air-driven clamping device; the pneumatic clamping device is a self-centering clamping device, and the repeated positioning precision is less than 2 mu m.
Further, in the system for coupling the optical fiber image sensing element with the photosensitive surface in the image sensor, the image sensor to be coupled is further fixed on the air-driven clamping device.
Further, in the system for coupling the optical fiber image sensing element with the photosensitive surface in the image sensor, the CMOS camera is a high-resolution large-objective CMOS camera, and the resolution is more than 500 ten thousand pixels.
Further, in the system for coupling the optical fiber image sensing element with the photosensitive surface in the image sensor, the heating device comprises at least one of a heating ring and a gas heating micropore spray pipe, and the vacuum adsorption device comprises a vacuum chuck and a vacuum pump which are connected with each other.
Further, in the system for coupling the optical fiber image sensing element with the photosensitive surface of the image sensor, the image sensor is disposed on a 360 ° rotation platform; the swing angle of the 360-degree rotary platform is +/-5 degrees.
Further, in the system for coupling the optical fiber image sensing element with the photosensitive surface in the image sensor, the computer is connected with the image sensor to be coupled through a camera data line; the 360-degree rotating platform and the X/Y-direction displacement platform are connected with a computer through a movement displacement data line.
Further, in the system for coupling the optical fiber image sensing element with the photosensitive surface in the image sensor, the mounting positions of the LED white light source and the uv light source are located at the right upper end of the optical fiber image sensing element; and a diffusion light sheet is arranged on the input end of the optical fiber image transmission element.
The aim and the technical problems of the invention are realized by adopting the following technical proposal. The invention provides a method for coupling an optical fiber image sensing element with a photosensitive surface in an image sensor, which comprises the following steps:
1) Preparation before coupling:
11 Mounting the optical fiber image transmission element on a bracket and clamping by using an air-driven clamping device;
12 Connecting the CMOS camera, the 360-degree rotating platform and the X/Y displacement platform with a computer, opening the computer, and starting the control of the coupling of the optical fiber image transmission element;
13 Inspection of the LED light source and the uv light source;
2) Removing the glass cover plate:
21 Arranging the image sensor on a 360-degree rotary platform, fixing the shell of the image sensor by using an air-driven clamping device, and enabling the photosensitive surface of a chip to face upwards and face against the optical fiber image transmission element; connecting the image sensor with a computer;
22 Heating a glass cover plate of a chip of the image sensor, and continuously vacuum-adsorbing the glass cover plate while heating;
23 After the glass cover plate is removed, the chip is sprayed at normal temperature;
3) Positioning of the coupling position:
31 Fixing the image sensor, shooting the photosensitive surface of the chip by using a CMOS camera arranged right above the image sensor, transmitting the shot image to a computer, selecting a coupling position on the photosensitive surface, and setting the coupling position as a position one;
32 The CMOS camera is removed, an LED light source arranged right above the optical fiber image transmission element is turned on, light is homogenized by a diffusion glass slide and then enters an input end, a light transmission surface is formed at the output end of the optical fiber image transmission element, the light transmission surface presents a corresponding image on an image sensor, a region coupled with a photosensitive surface is selected in a computer, the center of the light transmission surface is determined, the center is set as a second position, the second position is moved to the first position by the horizontal and strong movement controlled by the computer, and the positions are overlapped, so that the positioning of the coupling position is realized;
4) The light-transmitting surface is coupled with the photosensitive surface in a curing way:
41 In the direction vertical to the displacement platform, the optical fiber image transmission element is moved to the position right above the photosensitive surface of the chip of the image sensor through computer control, and the gap distance between the optical fiber image transmission element and the glass cover plate of the photosensitive surface is kept;
42 Continuously moving the optical fiber image transmission element towards the X/Y displacement platform until the optical fiber image transmission element is contacted with the photosensitive surface, obtaining acting force when the light-transmitting surface is coupled with the photosensitive surface through the pressure sensor, and triggering the coupling to stop at a pressure jump point, wherein the optical fiber image transmission element stops moving downwards; meanwhile, a real-time coupling result is obtained through monitoring of coupling resolution or relative transmittance;
43 Rotating the 360-degree rotary platform, and monitoring the coupling resolution or the relative transmittance result in real time; and then, an ultraviolet light source or a visible light source is turned on, the optical fiber image transmission element is irradiated from the input surface of the optical fiber image transmission element, and the light reaches a coupling interface to be subjected to optical rapid solidification, so that coupling is realized.
Further, in the aforementioned method for coupling the optical fiber image sensing element with the photosensitive surface of the image sensor, in step 22), heating the glass cover plate of the photosensitive surface of the chip of the image sensor specifically includes: and (3) sleeving the heating ring on a glass cover plate of a photosensitive surface of a chip of the image sensor, heating the whole bonding surface, and controlling the heating temperature to be not more than 80 degrees.
Further, in the aforementioned method for coupling the optical fiber image sensing element with the photosensitive surface in the image sensor, in step 31), selecting the coupling position on the photosensitive surface specifically includes: the coupling position on the photosensitive surface is selected according to the requirement, or the coupling position or area is determined by imaging of the image sensor, and is set as the central position by computer control.
Further, in the aforementioned method for coupling the optical fiber image sensing element to the photosensitive surface of the image sensor, in step 32), selecting the coupling position on the photosensitive surface according to the need includes: the photosensitive surface is rectangular, the output coupling of the optical fiber image transmission element is rectangular, and the position of the photosensitive surface is adjusted to correspond to the output surface of the optical fiber image transmission element, so that the complete correspondence between the rectangular edge and the corner is realized.
Further, in the method for coupling the optical fiber image sensing element with the photosensitive surface in the image sensor, in step 32), the transmitting surface of the optical fiber image sensing element is a surface coupled with the photosensitive surface.
Further, in the method for coupling the optical fiber image sensing element to the photosensitive surface of the image sensor, in step 41), after maintaining a distance from the photosensitive surface of the chip, the method further includes: and uniformly coating coupling photosensitive curing glue or matching liquid on the output surface of the optical fiber image transmission element.
Further, in the aforementioned method for coupling the optical fiber image sensing element to the photosensitive surface in the image sensor, in step 43), the rotation is stopped when the coupling resolution or the relative transmittance reaches a maximum value; meanwhile, observing the image of the coupling surface in the display of the computer, and when the coupling surface has a gap, finely adjusting the swing angle of the 360-degree rotating platform until the coupling surface has no gap.
Further, in the method for coupling the optical fiber image sensing element with the photosensitive surface of the image sensor, in the step 4), the rapid optical curing includes: and turning on an ultraviolet light source, and irradiating ultraviolet light onto the photosensitive adhesive through the optical fiber image transmission element to perform rapid solidification.
Compared with the prior art, the system and the method for coupling the optical fiber image sensing element with the photosensitive surface in the image sensor have the following beneficial effects:
has the functions of solidification coupling, real-time monitoring of coupling effect and detection: the system and the method provided by the invention not only can realize the optical curing coupling of the optical fiber image transmission element and the image sensor, but also can evaluate the coupling effect in real time by detecting indexes such as coupling resolution or relative transmittance. Besides the coupling function, the system and the method can also be used for detecting indexes such as relative light transmittance, imaging distortion and the like of imaging of the optical fiber image sensing element and the image sensor.
High-precision rapid coupling: the system and the method provided by the invention adopt a high-precision mobile platform and a high-resolution camera. Through the accurate positioning of the X, Y direction of the optical fiber image transmission element position and the accurate positioning of the X, Y direction of the photosensitive surface of the image sensor, then the X/Y displacement platform is moved to realize the superposition of the optical fiber image transmission element and the photosensitive surface in the X, Y direction, and the optical fiber image transmission element is automatically and controllably moved in the direction vertical to the displacement platform to realize the coupling of the optical fiber image transmission element and the photosensitive surface. The coupling medium adopts fast curing photosensitive adhesive, and the coupling medium is cured within 10-30 seconds under the irradiation of ultraviolet light or visible light.
Has the function of removing the glass cover plate on the photosensitive surface: the invention can realize the heating function of the directional position and the function of heating and removing the glass cover plate on the photosensitive surface by arranging a set of precisely controlled heating device. Meanwhile, the auxiliary high-vacuum adsorption device can easily remove the glass cover plate from the photosensitive surface of the image sensor, so that the problem of surface pollution caused by removal and coupling separation is avoided.
The foregoing description is only an overview of the present invention, and is intended to provide a more thorough understanding of the present invention, and is to be accorded the full scope of the present invention.
Drawings
FIG. 1 is a schematic diagram of a system for coupling an optical fiber image sensing element to a photosensitive surface in an image sensor according to the present invention;
FIG. 2A is a schematic diagram of a displacement platform for a system for coupling an optical fiber image sensing element to a photosurface in an image sensor according to the present invention;
FIG. 2B is a cross-sectional view A-A of FIG. 2A;
FIG. 3 is a schematic diagram of a heating unit for a system for coupling an optical fiber image sensing element to a photosensitive surface in an image sensor according to the present invention;
FIG. 4 is a schematic diagram of a vacuum suction device for a system for coupling an optical fiber image sensing element to a photosensitive surface in an image sensor according to the present invention;
FIG. 5 is a schematic diagram of UV fast curing coupling in accordance with the present invention;
FIG. 6 is a schematic illustration of the glass cover plate of the present invention removed;
FIG. 7 is a schematic diagram of a coupling structure of embodiment 1 of the present invention;
FIG. 8 is a schematic diagram of a coupling structure of embodiment 2 of the present invention;
FIG. 9 is a schematic diagram of a coupling structure of embodiment 3 of the present invention;
FIG. 10A is a graph showing the coupling resolution test result of embodiment 1 of the present invention;
FIG. 10B is a graph showing the coupling resolution test result of embodiment 2 of the present invention;
FIG. 10C is a graph showing the coupling resolution test result of example 3 of the present invention;
FIG. 11A is a graph showing the results of the relative transmittance test in example 1 of the present invention;
FIG. 11B is a graph showing the relative transmittance test results of example 2 of the present invention;
FIG. 11C is a graph showing the results of the relative transmittance test in example 3 of the present invention;
FIG. 12A is a graph showing the result of the light transmittance uniformity test in example 1 of the present invention;
FIG. 12B is a graph showing the result of the light transmittance uniformity test in example 2 of the present invention;
FIG. 12C is a graph showing the result of the light transmittance uniformity test in example 3 of the present invention.
Detailed Description
In order to further describe the technical means and effects of the present invention for achieving the intended purpose, the following describes the specific implementation, structure, characteristics and effects of the system and method for coupling an optical fiber image sensor to a photosensitive surface in an image sensor according to the present invention in combination with the preferred embodiments. In the following description, different "an embodiment" or "an embodiment" do not necessarily refer to the same embodiment. Furthermore, the particular features, structures, or characteristics of one or more embodiments may be combined in any suitable manner.
The following materials, unless otherwise specified, are all commercially available.
As shown in fig. 1-4, the present invention provides a system for coupling an optical fiber image sensing element to a photosensitive surface in an image sensor, comprising:
The main structure unit comprises a left bracket 2, a right bracket 3, a light shield 1 and a base 18, wherein the left bracket 2 and the right bracket 3 are fixed on the surface of the base 18 through screws, the left bracket 2, the right bracket 3 and the base 18 are arranged in the light shield 1, the light shield 1 is a stainless steel metal cabinet, and the inner wall of the cabinet body is coated with carbon black nitrolacquer with the thickness of 0.05mm-0.1 mm; the left bracket 2 and the right bracket 3 are made of stainless steel, the base 18 is made of marble materials, and marble platforms with different sizes can be selected according to the size of the defect detection batch in actual use; the light shield 1 is made of stainless steel sheets, the inner surface and the outer surface of the light shield are coated with black light absorbing materials (such as carbon black nitrolacquer) with the thickness of 0.15mm-0.2mm, the absorptivity of the light shield to external stray light is more than 98%, the reactivity (measured by a spectrophotometer) to the light source in the light shield is less than 2%, and the influence of external light and internal light on the monitoring light intensity in the coupling process is avoided. The main structural unit is a framework of the whole system.
A displacement positioning unit including a CMOS camera 10, a 360 ° rotation stage 16, and an X/Y displacement stage 17; the CMOS camera 10 is connected to the right bracket 3 through a tightening screw, the CMOS camera 10 is a high-resolution large-objective CMOS camera, and the resolution of the CMOS camera is more than 500 ten thousand pixels; an auxiliary light source 11 is installed at the lower end of the CMOS camera 10, the auxiliary light source 11 comprises two white LED lamps, and when the image sensor 15 to be coupled is photographed or the glass cover plate 13 is removed, the ambient light is dark, so that light can be supplemented; the 360-degree rotating platform 16 is arranged on the X/Y-shaped displacement platform 17 and is connected with the X/Y-shaped displacement platform 17 through four screws, and the X/Y-shaped displacement platform 17 is fixed on the base 18 through the screws; the X/Y displacement platform 17 includes two metal frames 26 that separate up and down, and two sets of positioning grating rulers 23, two sets of stepper motors 24 and two sets of precision screws 25, the metal frame 26 that sets up below is placed on the base 18, two triangle-shaped recesses 27 have been seted up on the metal frame 26, two triangle-shaped protruding that correspond with two triangle-shaped recesses 27 have been seted up to the metal frame 26 that sets up above, just two when triangle-shaped recesses 27 and two triangle-shaped protruding contact form the microgap that is less than 1mm for two metal frames 26 can carry out relative movement. The positioning grating ruler 23 is respectively connected with two metal frames 26, the two groups of stepping motors 24 are connected with two groups of precise screws 25, the two groups of precise screws 25 are connected with two triangular grooves 27, and the precise screws rotate to drive the grooves 27 to move; the moving distance is precisely measured through the positioning grating ruler 23 and is mutually cooperated with the displacement size of the metal frame, so that precise coupling positioning is realized; high-precision displacement in the X and Y directions and acquisition of high-definition images can be realized (see fig. 2A and 2B). The image and displacement data are transmitted to the computer 20, and the CMOS camera 10, the 360-degree rotating platform 16 and the X/Y displacement platform 17 are linked, so that high-precision positioning is realized, and the accuracy of the coupling position is ensured.
The positioning heating unit comprises a temperature control meter 28, a heating device and a vacuum adsorption device, wherein the temperature control meter 28, the heating device and the vacuum adsorption device are arranged outside the main body structural unit, the heating device can be at least one of a heating ring 12 and a gas heating microporous spray pipe 29, and the vacuum adsorption device can comprise a vacuum chuck 30 and a vacuum pump 31 which are connected with each other, as shown in fig. 4; in specific implementation, the heating device is placed on the glass cover plate of the chip of the image sensor 15, so as to directionally heat the bonding position of the glass cover plate and the main board of the image sensor 15, and meanwhile, the vacuum adsorption device is used for vacuum adsorption (the vacuum degree is 0.01-0.1 Pa) on the glass cover plate, and when the temperature reaches the temperature required by degumming, the vacuum adsorption device can directly suck away the glass cover plate.
An optical fiber transmission element clamping unit comprises an air drive clamping device 8, a resolution/shearing standard template 6 and a knob7 and a pressure sensor 21; one side of the air-driven clamping device 8 is fixed on the left bracket 2, a pressure sensor 21 is fixed on the other side of the air-driven clamping device 8, the air-driven clamping device 8 is a self-centering fixing frame, and can clamp optical fiber image transmission elements with the diameter of 5-200 mm, and the air-driven clamping device comprises an optical fiber image inverter, an optical fiber panel, an optical fiber image inverter or regular polygons such as squares and rectangles with equivalent sizes and special-shaped optical fiber image transmission elements with equivalent sizes. One side of the knob 7 is connected with an LED white light source, the other side is connected with the right bracket 3, and the resolution/shearing standard template 6 is arranged on the input surface of the optical fiber image transmission element 9, and generally refers to one end with a larger diameter. Under illumination, the pattern on the resolution/shear master template 6 may be presented at the other end by a fiber optic image-transmitting element 9. When the optical fiber image transmission element 9 is coupled with the photosensitive surface of the chip, an optimal coupling position and an optimal coupling angle exist, and the thickness of the coupling optical adhesive of the coupling interface and the influence of the coupling optical adhesive on the coupling effect are also needed to be known. The resolution image on the computer screen is observed in real time during coupling, and the image sensor 15 is moved, and the highest resolution value is obtained, namely the optimal coupling position is considered. The invention uses the pressure sensor to realize the monitoring of the pressure of the coupling interface, combines the real-time detection of the resolution and the transmissivity to obtain the optimal thickness of the interface optical adhesive, and can avoid the damage to the chip caused by the overlarge interface pressure, so the thickness of the designed interface optical adhesive is not more than 20 mu m, and the interface pressure is suitably 0.01-0.1Kg/cm 2 Between them.
A monitor display unit including a computer 20 (including a display), a camera, a movement displacement data line 19, and the like; the computer 20 is connected with an image sensor 15 to be coupled through a camera data line 19, the image sensor 15 can be a CCD or CMOS camera, and is arranged on a 360-degree rotating platform 16, the 360-degree rotating platform 16 and an X/Y displacement platform 17 are connected with the computer 20 through a motion displacement data line 19, a motion precision control module and a luminance analysis module are arranged in the computer 20, the motion precision control module is operated on the computer 20 to realize the precise control of displacement, and the center position (namely the center of the coupling position) is determined through the identification of the CMOS camera 10. The unit mainly monitors the resolution and the transmittance (brightness) in the coupling process in real time, and adjusts the coupling position and angle in real time according to the monitoring result. Specifically, the image sensor 15 to be coupled is coupled with the optical fiber image transmission element 9 at an optimal coupling angle or position, and the optimal coupling angle with the optical fiber image transmission element 9 is found by rotating the 360-degree rotating platform 16; the resolution image on the screen of the computer 20 is observed in real time during coupling, and the image sensor 15 is moved to obtain the highest resolution value, namely the optimal coupling position. Meanwhile, the 360-degree rotary platform 16 also has a swinging function with a certain angle, wherein the swinging angle is +/-5 degrees, so that the device is suitable for the situations that different coupling positions have different levelness and the optical fiber image transmission element 9 is clamped to be not horizontal so as to generate a coupling gap. And
A light source unit including an LED white light source 4, an ultraviolet light source 5, and a light source controller; the LED white light source 4 is arranged on the right bracket 3, and the LED white light source 4 is an illumination light source for standard template imaging; the ultraviolet light source 5 is arranged on the left bracket 2, and the ultraviolet light source 5 is a fast-curing irradiation light source; the light source controller is arranged outside the main body structure unit so as to facilitate adjustment during testing. In implementation, as shown in fig. 5, the mounting positions of the LED white light source 4 and the ultraviolet light source 5 are located at the right upper end of the optical fiber image transmission element 9, and for the purpose of uniform light source, a milky-white diffusion light sheet 31 is placed on the input end of the optical fiber image transmission element 9, so as to achieve the purpose of uniform light source, and a uniform incident light source is required for both imaging and curing.
The invention also provides a method for coupling the optical fiber image sensing element with the photosensitive surface in the image sensor, which comprises the following steps:
1) Preparation before coupling:
a) The optical fiber image transmission element 9 is arranged on a fixed bracket and is clamped by an air-driven clamping device 8, and the repeated positioning precision of the clamping device is less than 2 mu m; the optical fiber image transmission element 9 can be an optical fiber light cone, an optical fiber panel, an optical fiber image inverter and the like;
b) The CMOS camera 10, the 360-degree rotating platform 16, the X/Y displacement platform 17 and the data line 19 of the 360-degree rotating platform 16 and the computer 20 are connected, the computer 20 is opened, and the control of the coupling of the optical fiber image transmission elements is started;
c) The LED white light source 4 and the uv light source 5 are inspected, wherein the uv light source 5 can switch the light sources of different uv bands as required, and the typical uv wavelength is 365nm. In order to achieve uniform incidence of light, the light is generally matched with a milky diffusion sheet 32 (made of quartz material) and placed on the input surface of the optical fiber image transmission element 9, and the light passes through the diffusion sheet 32 and then enters the optical fiber image transmission element 9, as shown in fig. 5. The diffusion sheet 32 is directly attached to the optical fiber image transmission element 9, and if the resolution/shearing standard template 6 is installed on the input surface of the optical fiber image transmission element 9, the diffusion sheet 32 is directly arranged on the resolution/shearing standard template 6.
2) The glass cover plate was removed, see fig. 6:
a) The image sensor 15 is placed on a 360-degree rotary platform 16, the housing of the image sensor 15 is fixed by the air-driven clamping device 8, and the photosensitive surface 14 of the chip of the image sensor 15 faces upwards and faces the optical fiber image transmission element 9. If the chip of the image sensor 15 cannot be completely exposed outside, it is necessary to disassemble the casing of the image sensor 15 partially to ensure that the photosensitive surface of the chip is completely visible, and there is a certain space for performing the heating and removing operation. Meanwhile, the CMOS camera 10 is connected to a computer 20 with a data line 19.
b) A heating device such as a heating ring 12 is sleeved on a glass cover plate 13, the whole bonding surface is heated, the temperature is controlled to be not more than 80 ℃, the degumming temperatures of different glues are different, and the maximum temperature is set on the principle of not damaging a camera chip. The bonding surface refers to the bonding surface of the glass cover plate and the photosensitive surface of the chip. While heating, a vacuum suction device such as a vacuum chuck 30 is applied to the glass cover 13 to ensure that the degumming temperature used is low. For the local position not easy to degum, the microporous spray pipe 29 can be heated by air heating, and the inner diameter of the spray pipe is smaller than 1mm. Specifically, when the bonding surface is heated, the adhesive is removed after reaching a certain temperature, the glass cover plate and the chip are separated, suction force is always applied to the glass cover plate in the process, and the adhesive is removed once the adhesive is removed.
c) After the glass cover plate is removed, the air heating microporous spray pipe 29 sprays ionized purified air at normal temperature, and can prevent static electricity from gathering while blowing the photosensitive surface (mainly for removing pollutants such as dust in the adsorption environment of the photosensitive surface of the chip).
3) Positioning of the coupling position:
a) The image sensor 15 is fixed by the self-centering clamping device 8, the self-centering clamping device 8 is fastened on a 360-degree rotating platform by a screw 22, the photosensitive surface 14 of a chip of the image sensor 15 is imaged by the CMOS camera 10 arranged right above the image sensor 15 and transmitted to a motion precise control module of the computer 20, and the coupling position on the photosensitive surface is selected according to the requirement. Specifically, the shape of the photosensitive surface of the chip and the shape of the output coupling surface of the optical fiber image sensor 9 determine the coupling position. For example, the photosensitive surface is rectangular, and the output coupling of the optical fiber image sensor 9 is also rectangular, so that the position of the photosensitive surface needs to be adjusted to adapt to the output surface of the optical fiber image sensor 9, so as to realize the complete correspondence between the rectangular sides and the corners. The position or area of the coupling can also be determined by imaging the image sensor 15 itself and by controlling the central position of the coupling set as the photosurface by the motion precision control module as position one.
b) The CMOS camera 10 disposed above the chip is moved upward in a direction perpendicular to the X/Y displacement stage 17, the LED white light source 4 disposed directly above the optical fiber image transmission element 9 is turned on, the light is homogenized by the diffusion sheet 32 and then incident on the input surface of the optical fiber image transmission element 9, and the light is output on the output surface 34 of the optical fiber image transmission element, that is, the surface coupled with the photosensitive surface 14 (see fig. 5). The output surface 34 will present a corresponding image on the CMOS camera 10 above, and select the area coupled with the photosensitive surface in the motion precision control module of the computer 20, and determine the center thereof, set as the second position, and move the first position to the second position under the control of the motion precision control module of the computer 20, and the positions coincide, so as to realize the preliminary positioning of the coupling position.
4) The light transmitting surface is solidification coupled with the photosensitive surface, see fig. 5:
a) After the first coupling position and the double coupling, the double coupling is realized only in the X, Y direction. The optical fiber image transmission element 9 is moved downwards to the position right above the chip of the image sensor 15 by the motion precision control module of the computer 20, the photosensitive surface of the chip is kept to be not smaller than 5mm, at the moment, the output surface 34 of the optical fiber image transmission element 9 is uniformly coated with photosensitive curing glue or matching liquid, and the coating thickness is not more than 20 mu m. The coupling glue layer 33 may be formed after the photosensitive curing glue is applied. The coupling can be directly performed according to the coupling process design without coating any coupling glue on the output surface 34 of the optical fiber image transmission element 9.
b) The fiber optic element 9 continues to be moved perpendicular to the X/Y displacement stage 17 until it contacts the photosurface 14. The force when the output surface 34 is coupled with the photosensitive surface 14 is obtained by the pressure sensor 21 arranged at one side of the gas-driven clamping device 8, and the resistance sudden increase point triggers the coupling to stop so as to ensure that the photosensitive surface is not damaged. Meanwhile, a real-time coupling result is obtained through monitoring of coupling resolution and transmittance. When the output surface 34 of the optical fiber image transmission element is circular, the platform 16 is rotated by 360 degrees to obtain the optimal coupling angle between the single optical fiber and the pixel, and when the resolution or the transmittance reaches the maximum value, the optimal coupling position is noted. When the light source is used, the door of the light shield 1 should be closed, so that the influence of external light on the detection result is avoided.
c) After the coupling result of the optimal resolution or transmittance is obtained, the ultraviolet light source 5 is turned on, and the ultraviolet light with the wavelength of 260-365nm can be irradiated onto the photosensitive curing glue (ultraviolet light-sensitive curing glue) through the optical fiber image transmission element 9 to form the coupling glue layer 33 so as to realize ultraviolet rapid curing (10-30 seconds). When the non-photosensitive curing adhesive (transparent epoxy resin adhesive) is selected, the coupling surface of the output surface of the optical fiber image transmission element and the photosensitive surface of the chip can be heated to not more than 100 ℃ through the heating ring 12, and the accelerated curing can be realized within 1-2 hours. Note that when the ultraviolet light source 5 is used, the door of the shade 1 should be closed to avoid injury of the operator by ultraviolet rays. In the process of real-time monitoring coupling, imaging a resolution standard template 6 on a display screen of a computer 20, identifying the image to obtain a line pair number on the image, wherein the position with a larger resolution value is the optimal position; similarly, if the transmittance is used, the resolution standard template 6 is not needed, the gray value of the image of the display screen is changed, and the position with higher luminance is the best position.
The system and the method for coupling the optical fiber image transmission element with the CCD or the CMOS have the following advantages:
1) Fast cure coupling (see fig. 5): the photo-curing optical adhesive is adopted, the adhesive can be rapidly cured under the irradiation of an ultraviolet light source 5 (300-380 nm) to form a coupling adhesive layer 33, and the refractive index n of the optical adhesive D The curing process can be completed within 30 seconds within 1.5-1.7, and the ultraviolet light source 5 is light homogenized by the diffusion sheet 32 and is emitted through the output surface 34 of the optical fiber image transmission element; bonding the optical fiber image transmission element 9 and the photosensitive surface of the chip of the image sensor 15 together by curing, the shearing strength is not less than 90Kg/cm 2 . The photosensitive adhesive preferably having a high refractive index, e.g. n D And the curing time is short, so that the light loss of interface coupling can be reduced, the controllability of the coupling process is improved, and the coupling precision is improved. In order to further reduce the reflection loss of the coupling interface, coupling matching liquid (commercially available mixed liquid of diiodomethane and sulfur) and photosensitive curing glue can be used for jointly coupling the optical fiber image transmission element and the photosensitive surface of the CCD or the CMOS. Refractive index n of matching liquid D Can reach approximately 1.8, and the value of the coupling optical imaging device is equivalent to the refractive index of glass of the optical fiber image transmission element, so that the coupling light transmittance can be obviously improved (for example, the coupling optical imaging device is improved by 10-15 percent), and clearer coupling imaging is obtained (the resolution can be improved by about 5 percent).
2) High-precision coupling: the invention adopts a high-precision displacement platform, and the movement precision and the repeated positioning precision can reach 2 mu m or less. The high-definition CMOS camera 10 (more than 500 ten thousand pixels) is assisted to realize image positioning, obtain an image of a coupled photosensitive surface, realize the identification of a central position through a characteristic position, and also realize the coupling of a specific position according to the requirement. Meanwhile, for positioning the coupling surface of the optical fiber image transmission element, the light transmission surface of the optical fiber image transmission element is obtained through the coupled image sensor, and the center of the light transmission surface is obtained through boundary identification. The center of the photosensitive surface and the center of the light-transmitting surface are overlapped by moving the displacement platform. For accurate positioning of the coupling angle, the multifilament boundary (generally, the secondary multifilament boundary) of the optical fiber image transmission element and the photosensitive image element are ideally coupled before coupling and curing mainly through the high-precision 360-degree rotating platform 16, so that the coupling between the single optical fiber in the optical fiber image transmission element and the photosensitive image element is optimal. The coupling angle is changed by rotating the platform 16 by 360 degrees, and when the monitored resolution value or transmittance reaches the highest, the optimal coupling angle is the ideal coupling.
3) Real-time monitoring and detection function: how to obtain the best coupling efficiency when the optical fiber image transmission element is coupled is a difficulty. Because the light transmission surfaces of the chip and the optical fiber image transmission element are likely to be damaged by correction after coupling and solidification, the coupling is generally carried out at one time, and the coupling efficiency is often dependent on coupling experience. In order to observe the coupling effect in real time, two monitoring logarithms are arranged, namely coupling resolution and the relative light intensity (luminance value) coupled out to a photosensitive surface. The coupling resolution is that the input end of the optical fiber image transmission element is irradiated by the LED light source, the input end is clung to the standard resolution target, the pattern on the standard template is imaged on the display screen by the coupled image sensor, and the optimal coupling position is determined by real-time image analysis. The coupled relative light intensity, the LED light source directly enters the light cone input end, the light enters the image sensor through the light cone and the coupling surface, a real-time picture is obtained on the display screen of the computer, a region is selected, and the luminance value of the region is displayed in real time. The intensity of the light is represented by the intensity of the luminance value, and the larger the luminance value is, namely the higher the transmittance is, the larger the light intensity can be represented.
4) The chip glass cover plate can be removed (see fig. 6): when the optical fiber image sensing element 9 is coupled to the image sensor 15, the output surface 34 of the optical fiber image sensing element needs to be directly contacted with the photosensitive surface 14 on the chip or coupled through glue. Typically, the glass cover plate 13 on the chip is also left and is very strong by gluing. It is also a difficulty to remove the glass cover 13 by dissolving the glue layer with a solvent, and also to remove the glue layer by heating, both of which may cause damage to the chip. In order to avoid damage to other parts of the chip, the invention adopts directional heating (not exceeding 80 ℃) and places the heating ring 12 above the glass cover plate 13, the heating ring 12 can be manufactured according to the shape and the size of the glass cover plate 13, for example, the heating ring 12 is obtained by sleeving a resistance wire in a ceramic ring or a soft rubber ring, and meanwhile, the micro-pore spray pipe 29 is heated by air in an auxiliary specific position. During the heating process, the vacuum chuck 30 is opened to continuously act on the glass cover plate 13, and the degummed glass cover plate 13 is sucked away in time.
The working principle of the system of the invention is as follows: the coupling of the optical fiber image transmission element 9 and the image sensor 15 is not simply adhesion and curing or physical contact coupling, and the coupling has high coupling efficiency, high light transmittance and coupling resolution. Based on the basic principle that optical fiber wires of an optical fiber image transmission element unit are in one-to-one correspondence with pixels of a photosensitive surface (or a plurality of unit optical fibers are in correspondence with one pixel), a high-precision positioning and displacement unit and a multi-angle multi-azimuth coupling position adjusting device are designed, a rapid curing mode is adopted, the accuracy of the coupling positions of the optical fiber image transmission element 9 and the photosensitive surface 14 is ensured, in the coupling process, an on-line relative transmittance and resolution test and a temperature and interface pressure monitoring unit are realized, an ideal coupling position is found in an auxiliary mode, and physical damage and thermal damage to the chip surface in the coupling process are avoided. Therefore, the method not only can realize high-precision solidification coupling, but also can monitor the coupling function in real time. In addition, aiming at the problem that the chip protection glass cover plate of the image sensor is difficult to dismantle, the method also realizes the coupling of dismantling the glass cover plate, high precision, high resolution and high transmission and online real-time monitoring of the coupling performance through the heating device. Based on the working principle, the coupling with the micron-level precision can be realized, the real-time monitoring of the coupling process is realized, and the negative influence of the coupling operation on the imaging quality of the optical fiber imaging element and the imaging sensor is reduced. Meanwhile, the system and the method basically integrate all coupling flows, so that the influence of the external environment on the coupling is reduced, and the high-efficiency coupling is facilitated.
The invention will be further illustrated with reference to the following examples.
Example 1
The coupling sample is a fiber light cone and a CCD camera.
The specification of the optical fiber cone is as follows: the diameter of the big end is 49mm, and the effective diameter is 44.6mm; the diameter of the small end is 20 multiplied by 11mm, the effective size is 19.5 multiplied by 10.8mm, the amplification ratio is 2:1, and the unit wire diameter is 6 mu m (the large end).
The photosurface of the CCD camera is 19.5X10.8 mm, and the pixel size is 10×10μm.
The photosensitive surface of the chip is arranged at the lower part of the output surface of the optical cone of the optical fiber.
Coupling photosensitive adhesive: refractive index n D 1.55; colorless and transparent; adhesive strength>90Kg/cm 2 The method comprises the steps of carrying out a first treatment on the surface of the Visible transmittance>90％。
Photo-curing wavelength: about 320nm; photo-curing time: 5-10s;
the system for coupling an optical fiber image sensing element with a photosensitive surface in an image sensor of the present embodiment includes:
the main body structure unit comprises a light shield 1, a left bracket 2, a right bracket 3 and a base 18 which are arranged in the light shield 1; the left bracket 2 and the right bracket 3 are respectively fixed on the base 18; the left support 2 and the right support 3 are made of stainless steel, the base 18 is a marble optical vibration isolation platform, and the material of the base can be granite materials with the flatness of 00 or more levels, so that the accuracy and the stability of detection are improved;
a displacement positioning unit including a CMOS camera 10, a 360 ° rotation stage 16, and an X/Y displacement stage 17; the CMOS camera selects a high-definition large objective lens camera. The chip adopts a scientific sCMOS chip, the unit pixel is 5.3 multiplied by 5.3 mu m, the area size of the photosensitive surface is 13.3 multiplied by 13.3mm, and the pixels are 630 ten thousand; the CMOS camera 10 is arranged on a right bracket, the 360-degree rotating platform 16 is arranged on the X/Y displacement platform 17, and rotation of a chip part or a fixed sensor at any angle is realized; the X/Y displacement platform 17 is fixed on the base, and can realize displacement in the X, Y direction, wherein the displacement precision is 0.5 mu m, and the displacement maximum size is 250mm; the X/Y displacement platform 17 comprises two metal frames 26 which are arranged up and down separately, two groups of positioning grating rulers 23, two groups of stepping motors 24 and two groups of precise screws 25, wherein the metal frames 26 arranged below are placed on the base 18, and two triangular grooves 27 are formed in the metal frames 26; the metal frames 26 arranged on the upper surface are provided with two triangular protrusions corresponding to the two triangular grooves 27, and when the two triangular grooves 27 are contacted with the two triangular protrusions, a micro-gap smaller than 1mm is formed, so that the two metal frames 26 can relatively move. The positioning grating ruler 23 is respectively connected with two metal frames 26 so as to drive the metal frames 26 to move, the two groups of stepping motors 24 are connected with two groups of precise screws 25, the two groups of precise screws 25 are connected with two triangular grooves 27, the precise screws rotate so as to drive the grooves 27 to move, and the moving direction of the platform is limited by the two triangular grooves 27; in order to ensure high precision of test positioning and repeated positioning, the sensor of the positioning grating ruler 23 adopts a closed type, the measurement step distance (resolution) is better than 0.5 mu m, and the measurement precision is +/-2 mu m; the precision screw 25 adopts a ball screw, the precision grade is selected to be more than C5 grade, the guide rail operated by the screw is selected to be more than P grade precision, and the parallelism of the precision screw is not more than 2 mu m when the precision screw runs 300 mm; the stepper motor 24 is a reactive stepper motor, and the rated torque is selected to be greater than 0.45Nm because the load is not large.
The positioning heating unit comprises a temperature control meter 28, an air heating microporous spray pipe 29, a vacuum chuck 30 and a vacuum pump 31 which are arranged outside the main body structural unit;
the optical fiber image transmission element clamping unit comprises an air drive clamping device 8, a resolution/shearing standard template and a pressure sensor 21, wherein the air drive clamping device is a self-centering fixing frame and can only move up and down in the direction vertical to the displacement platform; the gas drive clamping device is provided with a displacement grating ruler;
a monitoring display unit comprising a computer 20, said computer 20 being connected to an image sensor 15 to be coupled; and
a light source unit including an LED white light source 4, an ultraviolet light source 5, and a light source controller; the LED white light source 4 is arranged on the right bracket 3, the ultraviolet light source 5 is arranged on the left bracket 2, and the light source controller is arranged outside the main body structural unit; the ultraviolet wavelength of the ultraviolet light source 5 is 365nm, and the ultraviolet lamp beads are of annular design, so that the purpose of uniform light is achieved; the LED white light source 4 also adopts a ring-shaped design to achieve the purpose of uniform irradiation, and the color temperature is regulated to 2650K.
Through the system, the advantages and disadvantages of the coupling quality can be judged in real time, and the characteristic performance index of the whole system can be measured:
Coupling resolution: 45lp/mm;
coupling relative transmittance: 47.2%, the specific test values are shown in Table 1;
uniformity of light transmission: 84.2%, the specific test values are shown in Table 2;
as shown in fig. 7, a coupling glue layer 33 is disposed between the image sensor 15 and the optical cone 35.
The resolution after coupling is shown in fig. 10A.
The light transmittance after coupling is shown in fig. 11A.
The transmittance uniformity after coupling is shown in fig. 12A.
Example 2
The coupling samples were fiber optic faceplate and CMOS camera.
The specification of the optical fiber panel is as follows: an outer diameter of 21.85mm and an effective diameter of 18.3mm; the filament diameter of the unit filament is 6 mu m.
The CMOS camera chip pixel is 5.5X15.5 μm, and the size of the photosensitive surface area is 12.7X19.6 mm.
The photosensitive surface of the chip is arranged in the light-transmitting surface of the optical fiber panel.
Coupling photosensitive adhesive: refractive index n D 1.7; average light transmittance of 500-550nm>98 percent; adhesive strength>70Kg/cm 2 ；
Photo-curing wavelength and time: ultraviolet wavelength 320-390nm, curing time: 20-30s;
the arrangement and positional relationship of the respective parts of the system are the same as those of embodiment 1.
Through the system, the advantages and disadvantages of the coupling quality can be judged in real time, and the characteristic performance index of the whole system can be measured:
resolution after coupling: 50.8lp/mm
Coupling relative transmittance: 44.4%, the specific test values are shown in Table 1;
uniformity of light transmission: 77.0%, the specific test values of which are shown in Table 2;
as shown in fig. 8, a coupling glue layer 33 is disposed between the image sensor 15 and the optical fiber panel 36.
The resolution after coupling is shown in fig. 10B.
The light transmittance after coupling is shown in fig. 11B.
The transmittance uniformity after coupling is shown by the pass of fig. 12B.
Example 3
The coupling samples were an inverter and a CMOS camera.
The specification of the optical fiber image inverter is as follows: the outer diameter is 19mm, and the effective diameter is 16.3mm. The output end of the image inverter is processed into a ring-shaped surface with the diameter of 16 multiplied by 14mm and the unit wire diameter is 6 mu m under the limit of the size of a CMOS chip.
Inverting angle: 180 ° ± 1 °;
the photosensitive surface of the chip is arranged in the light-transmitting surface of the optical fiber panel.
Coupling photosensitive adhesive: refractive index n D 1.7; average light transmittance of 500-550nm>98 percent; adhesive strength>70Kg/cm 2 ；
Photo-curing wavelength and time: ultraviolet wavelength 320-390nm, curing time: 5-10s;
the system is the same as in example 1 except for the CMOS camera. The CMOS camera adopts a scientific CMOS chip, the pixel is 6.5 multiplied by 6.5 mu m, the area size of the photosensitive surface is 16.6 multiplied by 14.0mm, and the pixel is 550 ten thousand.
Through the coupling system, the advantages and disadvantages of the coupling quality can be judged in real time, and the characteristic performance index of the whole system can be measured:
Resolution after coupling: 50lp/mm;
relative transmittance: 38.0%, the specific test values are shown in Table 1;
uniformity of light transmission: 72.4%, the specific test values are shown in Table 2;
as shown in fig. 9, a coupling glue layer 33 is disposed between the image sensor 15 and the optical fiber image inverter 37.
The resolution after coupling is shown in fig. 10C.
The light transmittance after coupling is shown in fig. 11C.
The transmittance uniformity after coupling is shown in fig. 12C.
Table 1 relative transmittance test data for inventive examples 1, 2, 3
Project Blank space Example 1 Example 2 Example 3
Luminance value (cd/m) 2 ) 968 457 430 368
Relative transmittance 47.2％ 44.4％ 38.0％
Table 2 light transmission uniformity test data for inventive examples 1, 2, 3
As can be seen from the data in fig. 11A-11C, fig. 12A-12C, table 1 and table 2, the ideal coupling between the optical fiber taper, the optical fiber panel and the optical fiber image inverter and the photosensitive surface of the chip in the image sensor can be realized by the coupling system and the method for the optical fiber image sensing element and the photosensitive surface of the image sensor, the coupling effect indexes such as relative transmittance, light transmission uniformity and the like in the coupling process can be obtained, the quantitative assessment of the process monitoring and the effect is realized, and conditions are created for engineering application.
In the foregoing embodiments, the descriptions of the embodiments are emphasized, and for parts of one embodiment that are not described in detail, reference may be made to related descriptions of other embodiments.
The numerical ranges recited herein include all numbers within the range and include any two of the range values within the range. The different values of the same index appearing in all embodiments of the invention can be combined arbitrarily to form a range value.
The technical features of the claims and/or the description of the present invention may be combined in a manner not limited to the combination of the claims by the relation of reference. The technical scheme obtained by combining the technical features in the claims and/or the specification is also the protection scope of the invention.
The above description is only of the preferred embodiments of the present invention, and is not intended to limit the present invention in any way, but any simple modification, equivalent variation and modification made to the above embodiments according to the technical substance of the present invention still fall within the scope of the technical solution of the present invention.

Claims (12)

1. A method for coupling an optical fiber image sensing element to a photosensitive surface in an image sensor, comprising the steps of:
1) Preparation before coupling:
11 Mounting the optical fiber image transmission element on a bracket and clamping by using an air-driven clamping device;
12 Connecting the CMOS camera, the 360-degree rotating platform and the X/Y displacement platform with a computer, opening the computer, and starting the control of the coupling of the optical fiber image transmission element;
13 Inspection of the LED light source and the uv light source;
2) Removing the glass cover plate:
21 Fixing the image sensor on a 360-degree rotary platform, fixing the shell of the image sensor by using an air-driven clamping device, and enabling the photosensitive surface of a chip to face upwards and face against the optical fiber image transmission element; connecting the image sensor with a computer;
22 Heating a glass cover plate of a chip of the image sensor, and continuously vacuum-adsorbing the glass cover plate while heating;
23 After the glass cover plate is removed, the chip is sprayed at normal temperature;
3) Positioning of the coupling position:
31 Fixing the image sensor, shooting the photosensitive surface of the chip by using a CMOS camera arranged right above the image sensor, transmitting the shot image to a computer, selecting a coupling position on the photosensitive surface, and setting the coupling position as a first position;
32 The CMOS camera is removed, an LED light source arranged right above the optical fiber image transmission element is turned on, light is homogenized by the diffusion sheet and then enters the input end, a light transmission surface is formed at the output end of the optical fiber image transmission element, the light transmission surface presents a corresponding image on the image sensor, a region coupled with the photosensitive surface is selected in a computer, the center of the light transmission surface is determined, the center of the light transmission surface is set as a second position, the first position is moved to the second position by controlling the mobile displacement platform through the computer, and the positions are overlapped, so that the positioning of the coupling position is realized;
4) The light-transmitting surface is coupled with the photosensitive surface in a curing way:
41 In the direction vertical to the displacement platform, the optical fiber image transmission element is moved to the position right above the photosensitive surface of the chip of the image sensor by computer control, and the distance between the optical fiber image transmission element and the glass cover plate of the photosensitive surface is kept;
42 Continuously moving the optical fiber image transmission element towards the X/Y displacement platform until the optical fiber image transmission element is contacted with the photosensitive surface, obtaining acting force when the light-transmitting surface is coupled with the photosensitive surface through the pressure sensor, and triggering the coupling to stop at a pressure jump point, wherein the optical fiber image transmission element stops moving downwards; meanwhile, a real-time coupling result is obtained through monitoring of coupling resolution or relative transmittance;
43 Rotating the 360-degree rotary platform, and monitoring the coupling resolution or the relative transmittance result in real time; then, an ultraviolet light source or a visible light source is turned on, the optical fiber image transmission element input surface is irradiated, and light reaches a coupling interface to be subjected to rapid optical curing, so that coupling is realized;
the method specifically comprises the following steps: stopping rotation when the coupling resolution or relative transmittance result reaches a maximum; meanwhile, observing an image of the coupling surface in a display of the computer, and when a gap exists in the coupling surface, finely adjusting the swing angle of the 360-degree rotating platform until the coupling surface has no gap; the rapid optical curing includes: and (3) turning on an ultraviolet light source or a white light source, and irradiating light to the photosensitive adhesive through the optical fiber image transmission element to perform rapid curing coupling.
2. The method for coupling an optical fiber image sensing element to a photosurface in an image sensor of claim 1 wherein, in step 22), heating the glass cover plate of the photosurface of the chip of the image sensor comprises: and placing the heating ring on a glass cover plate of a photosensitive surface of a chip of the image sensor, heating the whole bonding surface, and controlling the heating temperature to be not more than 80 degrees.
3. The method for coupling an optical fiber image sensor element to a photosurface in an image sensor of claim 1 wherein, in step 31), selecting a coupling location on the photosurface comprises: selecting a coupling position on the photosensitive surface according to the requirement, or determining a coupling position or a coupling region through imaging of the image sensor, and searching and setting the coupling position or the coupling region as a central position through a computer; in step 32), the light-transmitting surface of the optical fiber image-transmitting element is a surface coupled with the photosensitive surface.
4. The method for coupling a fiber optic imaging element to a photosurface in an image sensor of claim 1, wherein in step 41), after maintaining a separation distance from the photosurface, further comprises: and uniformly coating coupling photosensitive glue or matching liquid on the output surface of the optical fiber image transmission element.
5. A system for coupling a fiber optic imaging element to a photosurface in an image sensor for performing the method of any of claims 1-4, comprising:
the main body structure unit comprises a light shield, a left bracket, a right bracket and a base, wherein the left bracket, the right bracket and the base are arranged in the light shield; the left bracket and the right bracket are respectively fixed on the base;
the displacement positioning unit comprises a CMOS camera, a 360-degree rotary platform and an X/Y displacement platform; the CMOS camera is arranged on the right bracket, the 360-degree rotating platform is arranged on the X/Y displacement platform, and the X/Y displacement platform is fixed on the base;
the positioning heating unit comprises a temperature control meter, a heating device and a vacuum adsorption device which are arranged outside the main body structure unit;
the optical fiber transmission element clamping unit comprises an air drive clamping device, a resolution/shearing standard template and a pressure sensor;
the monitoring display unit comprises a computer and a data line, wherein the computer is connected with an image sensor to be coupled; and
the light source unit comprises an LED white light source, an ultraviolet light source and a light source controller; the LED white light source is arranged on the right bracket, the ultraviolet light source is arranged on the left bracket, and the light source controller is arranged outside the main body structure unit.
6. The system for coupling an optical fiber image sensor with a photosensitive surface in an image sensor according to claim 5, wherein the X/Y displacement platform comprises two metal frames arranged vertically separately, two sets of positioning grating scales, two sets of stepper motors and two sets of precision screws; the metal frame arranged below the base is arranged on the base, and two triangular grooves are formed in the metal frame; two triangular protrusions corresponding to the two triangular grooves are formed on the metal frame, and when the two triangular grooves are in contact with the two triangular protrusions, a micro-gap smaller than 1mm is formed.
7. The system for coupling an optical fiber image sensor with a photosensitive surface in an image sensor according to claim 5, wherein the optical fiber image sensor is fixed on the air-driven clamping device; the pneumatic clamping device is a self-centering clamping device, and the repeated positioning precision is less than 2 mu m; and the air-driven clamping device is also fixedly provided with an image sensor to be coupled.
8. The system for coupling a fiber optic imaging element to a photosurface in an image sensor of claim 5 wherein said CMOS camera is a high resolution large objective CMOS camera having a resolution of 500 ten thousand pixels or more.
9. The system for coupling an optical fiber image sensor to a photosensitive surface of an image sensor of claim 5, wherein said heating means comprises at least one of a heating ring and a heated micro-porous nozzle, and said vacuum suction means comprises a vacuum chuck and a vacuum pump connected to each other.
10. The system for coupling an optical fiber image sensor element to a photosensitive surface of an image sensor of claim 5, wherein the image sensor is disposed on a 360 ° rotating platform; the swing angle of the 360-degree rotary platform is +/-5 degrees.
11. The system for coupling an optical fiber image sensing element to a photosensitive surface of an image sensor of claim 5, wherein the computer is coupled to the image sensor to be coupled via a camera data line; the 360-degree rotating platform and the X/Y-direction displacement platform are connected with a computer through a movement displacement data line.
12. The system for coupling an optical fiber image sensor with a photosensitive surface in an image sensor as in claim 5, wherein the mounting locations of the LED white light source and the uv light source are located directly above the optical fiber image sensor; and a diffusion light sheet is arranged on the input end of the optical fiber image transmission element.
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CN115366526B (en) * 2022-08-24 2023-07-28 广东华中科技大学工业技术研究院 Thermal spraying positioning correction method and device for glass cover plate and glass cover plate laminating equipment

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3002620A1 (en) * 2014-10-03 2016-04-06 Thales Method for producing a coupling optic for a low-light image sensing system and associated coupling optic
CN108200312A (en) * 2017-12-12 2018-06-22 中北大学 A kind of light-field camera
CN110049217A (en) * 2019-04-18 2019-07-23 中国建筑材料科学研究总院有限公司 Imaging sensor, optical imaging system and production method
CN111650695A (en) * 2020-07-20 2020-09-11 哈尔滨工程大学 Space light-optical fiber coupling alignment method for optical fiber transmission characteristic measurement

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2017031568A1 (en) * 2015-08-24 2017-03-02 Titan Medical Inc. Method and apparatus for illuminating an object field imaged by a rectangular image sensor
US10666826B2 (en) * 2016-11-30 2020-05-26 Kyocera Document Solutions Inc. Reading module having reflection mirror array, image reading device comprising same, and image forming apparatus therewith
US20190068927A1 (en) * 2017-08-30 2019-02-28 Omnivision Technologies, Inc. Optical fiber transmission lines for ultra-small image sensors

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3002620A1 (en) * 2014-10-03 2016-04-06 Thales Method for producing a coupling optic for a low-light image sensing system and associated coupling optic
CN108200312A (en) * 2017-12-12 2018-06-22 中北大学 A kind of light-field camera
CN110049217A (en) * 2019-04-18 2019-07-23 中国建筑材料科学研究总院有限公司 Imaging sensor, optical imaging system and production method
CN111650695A (en) * 2020-07-20 2020-09-11 哈尔滨工程大学 Space light-optical fiber coupling alignment method for optical fiber transmission characteristic measurement

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