Camera chip and camera device

Abstract

The application discloses a camera chip and a camera device, wherein the camera chip comprises an imaging chip and an F-P gradient filter, the F-P gradient filter is integrally arranged on the surface of the imaging chip, the thickness of the F-P gradient filter gradually increases from one side to the other side, and the F-P gradient filter partially covers the surface of the imaging chip. The technical scheme of the application can realize ordinary imaging and spectral imaging simultaneously, and can reduce the requirements of push-broom spectral imaging on the push-broom speed and the attitude stability of a platform.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of imaging devices, in particular to a camera chip and a camera device. BACKGROUND

[0002] With the development of science and technology, spectral imaging technology is gradually applied to people's life, for example, integrating the camera capable of spectral imaging into a mobile phone to facilitate people to monitor the quality and safety of fruits, vegetables and meat at any time in life, and to take pictures of the skin to obtain health information of the human body. The imaging spectrometer based on linearly variable filter has simple structure, small size, high mechanical stability and thermal stability, and is particularly suitable for handheld devices such as mobile phones. However, these linearly variable filters cover the entire imaging area, without reference image and attitude information, resulting in very high requirements for the stability of push scanning. Moreover, due to the influence of spectral crosstalk, the spectral resolution of the spectral imaging of these camera chips is low, which is difficult to meet the needs of users.

[0003] The above content is only used to assist in understanding the technical solutions of the present application and does not represent the acknowledgement of the above content as prior art. SUMMARY

[0004] The main purpose of the present application is to provide a camera chip, which aims to reduce the requirements of push scanning spectral imaging on push scanning speed and platform attitude stability, and at the same time improve the spectral resolution of spectral imaging.

[0005] To achieve the above purpose, the camera chip provided by the present application comprises:

[0006] The imaging chip and the F-P variable filter are integrally arranged on the surface of the imaging chip, which reduces the distance between the F-P variable filter and the imaging chip, reduces the spectral crosstalk, and thus improves the spectral resolution; the thickness of the F-P variable filter gradually increases from one side to the other side, and the F-P variable filter partially covers the surface of the imaging chip, so that spectral imaging and ordinary imaging can be realized at the same time.

[0007] Optionally, the thickness of the F-P variable filter gradually changes linearly or stepwise from one side to the other side.

[0008] Optionally, the F-P variable filter comprises a Bragg mirror or a metal film mirror.

[0009] Optionally, the thicker side of the F-P variable filter is integrally provided with a long-pass filter away from the surface of the imaging chip, and the long-pass filter is used to filter high-order transmission peaks.

[0010] Optionally, the F-P gradient filter is formed on the surface of the imaging chip by vacuum plating; and / or the long-pass filter is formed on the thicker side surface of the F-P gradient filter by vacuum plating.

[0011] Optionally, the imaging chip is a black-and-white imaging chip or a color imaging chip.

[0012] Optionally, the imaging chip surface partially covered by the F-P gradient filter is used as a spectral imaging area, and the rest of the imaging chip surface is used as a normal imaging area, the normal image obtained by the normal imaging area is used as reference information of the spectral image obtained by the spectral imaging area, to reduce the requirement for push scan stability.

[0013] The application further provides a camera device, comprising a camera chip, the camera chip comprising an imaging chip and an F-P gradient filter, the F-P gradient filter being integrally arranged on the surface of the imaging chip, the thickness of the F-P gradient filter gradually increasing from one side to the other side, and the F-P gradient filter partially covering the surface of the imaging chip.

[0014] Optionally, the camera device is a handheld device or a drone.

[0015] Optionally, the camera device further comprises an attitude sensor, the attitude sensor being used to obtain attitude information of the camera device during imaging, and a processor of the camera device being used to correct the spectral image according to the attitude information, to further reduce the requirement for push scan speed and platform attitude stability.

[0016] In the technical scheme of the present application, the surface of the imaging chip is integrally provided with an F-P gradient filter. On the one hand, the thickness of the F-P gradient filter gradually increases from one side to the other side, and for the F-P gradient filter, the thickness at each position can determine the center transmission wavelength at the corresponding position, and as the thickness increases, the center transmission wavelength will move in the long wave direction, so that the F-P gradient filter with gradually increasing thickness can provide a series of narrow-band transmission light within a certain spectral range, so that high spectral resolution spectral imaging is possible. On the other hand, the F-P gradient filter is integrally arranged on the surface of the imaging chip, so that there is no gap between the F-P gradient filter and the imaging chip, so that there is almost no spectral crosstalk phenomenon between the F-P gradient filter and the imaging chip, thereby improving the spectral resolution of the camera chip spectral imaging. In addition, the F-P gradient filter partially covers the surface of the imaging chip to serve as a spectral imaging area, and the remaining part of the imaging chip serves as a normal imaging area, so that spectral imaging and normal imaging can be realized at the same time. Further, the normal image obtained by the normal imaging area can be used as reference information for the spectral image obtained by the spectral imaging area, so as to reduce the requirements for push-broom spectral imaging on push-broom speed and platform attitude stability. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor based on the drawings shown.

[0018] Figure 1 Structure diagram of the camera chip from one view angle in an embodiment of the present application;

[0019] Figure 2 Structure diagram of the camera chip from another view angle in an embodiment of the present application; Figure 1

[0020] Figure 3 Structure diagram of the camera chip from another view angle in an embodiment of the present application;

[0021] Figure 4 Structure diagram of the camera chip from another view angle in an embodiment of the present application; Figure 3

[0022] Figure 5 Figure 3

[0023] Figure 6 Structure diagram of the camera chip from another view angle in an embodiment of the present application;

[0024] ​​​​Figure 7 For Figure 6 In the middle of Figure 4 The spectrum of the position corresponding to the position of A;

[0025] Figure 8 Flow chart for the camera device of the present application to realize spectral imaging;

[0026] Figure 9 The structure diagram of an embodiment of the camera device of the present application.

[0027] Explanation of reference numerals:

[0028] Reference Name Reference Name 10 Imaging chip 11 Normal imaging area 12 Spectral imaging area 20 F-P gradient filter 21 Long pass filter 30 RGB filter 40 Optical lens 50 Processor 51 Normal image processor 52 Spectral image processor 60 Attitude sensor 70 A / D converter

[0029] The implementation, functional features and advantages of the present application will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0031] It should be noted that if the embodiments of the present application involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement condition, etc. between the components in a certain posture, and if the certain posture changes, the directional indications also change accordingly.

[0032] In addition, if the embodiments of the present application involve descriptions of “first”, “second”, etc., the descriptions of “first”, “second”, etc. are only for description purposes, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features with “first” and “second” can explicitly or implicitly include at least one of the features. In addition, “and / or” or “and / or” appearing throughout the text means that the three parallel schemes are included, for example, “A and / or B” includes A scheme, or B scheme, or A and B simultaneously satisfy the scheme. In addition, the technical solutions of each embodiment can be combined with each other, but it must be based on the realization of those skilled in the art, and when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, nor within the scope of protection claimed by the present application.

[0033] The present application proposes a camera chip.

[0034] ReferenceFigure 1 In an embodiment of the present application, the camera chip comprises:

[0035] an imaging chip 10, and

[0036] an F-P (Fabry-Perot) gradient filter 20, which is integrally arranged on the surface of the imaging chip 10, and the thickness of the F-P gradient filter 20 gradually increases from one side to the other side.

[0037] In the embodiment, the imaging chip 10 can be a black-and-white imaging chip 10 or a color imaging chip 10. In addition, the image sensor used by the imaging chip 10 can be a CCD image sensor or a CMOS image sensor, etc.

[0038] It can be understood that if the F-P gradient filter 20 and the imaging chip 10 are arranged separately, there will be a gap between the F-P gradient filter 20 and the imaging chip 10, which will cause different spectral bands to appear spectral aliasing, that is, spectral crosstalk will occur, thereby greatly reducing the spectral resolution of spectral imaging.

[0039] In the technical solution of the present application, the surface of the imaging chip 10 is integrally provided with the F-P gradient filter 20. On the one hand, the thickness of the F-P gradient filter 20 gradually increases from one side to the other side. For the F-P gradient filter 20, the thickness at each position can determine the center transmission wavelength at the corresponding position, and as the thickness increases, the center transmission wavelength will move in the long-wave direction. Therefore, the F-P gradient filter 20 with gradually increasing thickness can provide a series of narrow-band transmitted light within a certain spectral range, so that high-spectral-resolution spectral imaging is possible. On the other hand, the F-P gradient filter 20 is integrally arranged on the surface of the imaging chip 10, so that there is no gap between the F-P gradient filter 20 and the imaging chip 10, thereby almost no spectral crosstalk phenomenon exists between the F-P gradient filter 20 and the imaging chip 10, so that the spectral resolution of the camera chip for spectral imaging can be improved.

[0040] Optionally, the F-P gradient filter 20 is formed on the surface of the imaging chip 10 by vacuum plating. The vacuum plating process can realize stable combination of the F-P gradient filter 20 on the surface of the imaging chip 10, while almost no gap exists between the F-P gradient filter 20 and the imaging chip 10. However, the design is not limited to this, and in other embodiments, the F-P gradient filter 20 can also be formed on the surface of the imaging chip 10 by other processes, as long as the F-P gradient filter 20 and the imaging chip 10 can be integrally arranged.

[0041] For the technical solution of forming by vacuum plating, since the imaging chip 10 has polymer microlenses and color filters on the surface after leaving the factory, the polymer microlenses and color filters need to be cleaned away at the position of the vacuum-plated F-P gradient filter 20 before the vacuum-plating of the F-P gradient filter 20. However, the design is not limited thereto, and in other embodiments, the position where the F-P gradient filter 20 needs to be vacuum-plated can be reserved on the surface of the imaging chip 10 before the imaging chip 10 leaves the factory, that is, during the production of the imaging chip 10, so that the polymer microlenses and color filters do not cover this position.

[0042] Referring to Figure 3 In an embodiment, the thickness of the F-P gradient filter 20 linearly changes from one side to the other side, that is, the surface of the F-P gradient filter 20 away from the imaging chip 10 is provided as a plane extending obliquely from one side to the other side, so as to provide a series of continuously changing transmission wavelengths in a certain spectral range. However, the design is not limited thereto, and in other embodiments, referring to Figure 2 the thickness of the F-P gradient filter 20 can also stepwise change from one side to the other side, that is, the surface of the F-P gradient filter 20 away from the imaging chip 10 is provided as a stepped surface, so that a series of continuously changing transmission wavelengths in a certain spectral range can also be achieved.

[0043] In addition, optionally, the F-P gradient filter 20 includes a distributed Bragg reflector (DBR) or a metal film reflector. Generally, the F-P gradient filter 20 generally includes a light transmission layer, and a first reflector and a second reflector arranged on opposite surfaces of the light transmission layer, and the first reflector and the second reflector can both be provided as a DBR or a metal film reflector. The DBR can achieve higher reflectivity, and the metal film reflector has cost advantages. Further optionally, the metal used in the metal film reflector can be, but is not limited to, silver, aluminum, and the like, which have relatively high reflectivity.

[0044] For the F-P gradient filter 20, similar to the diffraction order of a grating, there are also transmission peaks at other working orders, resulting in that the wavelength band where the high-order transmission peak appears cannot be used, so that the working spectral range is very narrow. Specifically, for a single F-P gradient filter 20, the wavelength interval between two adjacent transmission peaks is referred to as a free spectral range (FSR), and under normal circumstances, the F-P gradient filter 20 can only work within one FSR range, and when exceeding one FSR range, the high-order transmission peak and the first-order transmission peak will appear at the same time, at which time the F-P gradient filter 20 cannot accurately filter the required wavelength. For example, referring to Figure 4 ,Figure 4 For Figure 2 In the spectrum of the position A (long-wave position), it can be seen that, in addition to the first-order transmission peak (#1), there are also second-order transmission peak (#2) and third-order transmission peak (#3) and other high-order transmission peaks on the spectrum, that is, in addition to the light energy of the wavelength corresponding to the first-order transmission peak being able to be transmitted through the F-P gradient filter 20, the light of the wavelength corresponding to the high-order transmission peak can also be transmitted through the F-P gradient filter 20, so that the required wavelength cannot be accurately filtered.

[0045] In addition, by comparing Figure 5 With Figure 4 , in combination Figure 3 It can be seen that Figure 5 Corresponding to the spectrum of the thinner side position of the F-P gradient filter 20, Figure 4 Corresponding to the spectrum of the thicker side position of the F-P gradient filter 20, Figure 5 There is only a first-order transmission peak (#1) in the spectrum, Figure 4 In addition to the first-order transmission peak (#1), there are also high-order transmission peaks (#2 and #3) in the spectrum, obviously, the working spectrum of the thicker side position of the F-P gradient filter 20 is more easily limited by the FSR.

[0046] To solve the problem that the working spectrum is limited by the FSR, referring to Figure 6 In an embodiment, a long-pass filter 21 is integrally arranged on the surface of the thicker side of the F-P gradient filter 20 away from the imaging chip 10. It can be understood that, for the F-P gradient filter 20, since the greater the thickness, the greater the central transmission wavelength corresponding to it, that is, the thicker side of the F-P gradient filter 20 corresponds to the long-wave position, and therefore the corresponding arrangement is the long-pass filter 21. Specifically, the long-pass filter 21 can filter out the high-order transmission peaks (see Figure 7 ) that appear on the thicker side of the F-P gradient filter 20, so as to remove the spectral signals outside the working spectrum, and further make the spectrum corresponding to the thinner side (short-wave position) and the thicker side (long-wave position) of the F-P gradient filter 20 both have only the corresponding first-order transmission peak (#1), so as to solve the problem that the working spectrum is limited by the FSR. It should be noted that the specific passable wavelength band of the long-pass filter 21 can be selected according to the actual wavelength required to be transmitted by the product, and the present application does not limit this.

[0047] Further, the long-pass filter 21 is formed on the thicker side surface of the F-P gradient filter 20 by vacuum plating. The vacuum plating process can realize stable combination of the long-pass filter 21 on the surface of the F-P gradient filter 20, and at the same time, there is almost no gap between the long-pass filter 21 and the F-P gradient filter 20. However, the design is not limited to this, and in other embodiments, the long-pass filter 21 can also be formed on the surface of the F-P gradient filter 20 by other processes, as long as the integration of the long-pass filter 21 and the F-P gradient filter 20 can be realized.

[0048] With reference to Figure 1 Or Figure 6 In this embodiment, the F-P gradient filter 20 partially covers the surface of the imaging chip 10 to serve as a spectral imaging area 12, and the remaining part of the imaging chip 10 serves as a normal imaging area; in this way, the camera chip provided by the present application can realize spectral imaging while performing normal imaging, that is, part of the obtained frame image is a spectral image and part is a normal image, so that only one camera with the camera chip of the present application needs to be installed on the camera equipment such as handheld devices and unmanned aerial vehicles to meet the needs of users for spectral imaging and normal imaging at the same time, without the need to install multiple cameras with different functions, thereby reducing the cost of these camera equipment and reducing the burden on consumers.

[0049] Further, the normal image obtained by the normal imaging area 11 can be used as reference information of the spectral image obtained by the spectral imaging area 12, that is, part of the normal image can be used as a reference for spectral imaging registration to reduce the requirements for push scanning speed and platform attitude stability of push scanning spectral imaging, thereby meeting the needs of applying the camera chip to camera equipment such as handheld devices (such as mobile phones, tablet computers, etc.) and unmanned aerial vehicles.

[0050] It should be noted that the push scanning speed of the special slitless push scanning linear gradient filter type spectral imaging system needs to be synchronized with the frame rate of the imaging chip, and the stability and speed of the scanning platform have very high requirements, which cannot be applied to camera equipment such as handheld devices and unmanned aerial vehicles that cannot be stably scanned. However, the camera chip provided by the present application can realize spectral imaging while performing normal imaging, and the normal image obtained by normal imaging can be used as a reference for displacement of the image on the imaging surface, and can be used to register the spectral image obtained by spectral imaging (see Figure 8 ).

[0051] Optionally, the thicker side of the F-P graded filter 20 is arranged close to the normal imaging area 11. That is, the thickness of the F-P graded filter 20 gradually increases in the direction close to the normal imaging area 11. However, the design is not limited thereto, and in other embodiments, the thicker side of the F-P graded filter can also be arranged away from the normal imaging area 11.

[0052] Further, the spectral imaging area 12 is smaller than the normal imaging area 11, so that the part of the normal image in the image formed by the camera chip can occupy a larger proportion. It can be understood that for ordinary users, the normal camera requirement is usually greater than the spectral imaging requirement. By arranging the normal imaging area 11 to be larger than the spectral imaging area 12, the normal camera function can be avoided from being excessively affected, thereby facilitating the needs of ordinary users. However, the design is not limited thereto, and in other embodiments, the spectral imaging area 12 can also be equal to or larger than the normal imaging area 11.

[0053] In addition, in the embodiment, the normal imaging area 11 and the spectral imaging area 12 are arranged on both sides of the surface of the imaging chip 10; however, the design is not limited thereto, and in other embodiments, the normal imaging area 11 and the spectral imaging area 12 can also have other distribution manners, for example, but not limited to, the normal imaging area 11 is arranged inside the spectral imaging area 12.

[0054] The present application also proposes a camera device, which comprises a camera chip, and the specific structure of the camera chip is referred to the above embodiments. Since the camera device adopts all the technical solutions of the above embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, which will not be repeated here. In the present application, the camera device can be, but is not limited to, a handheld device, a drone, etc. The handheld device can be, but is not limited to, a mobile phone, a tablet computer, etc.

[0055] Reference Figure 9In an embodiment, the camera device further comprises an optical lens 40, an A / D converter 70 and a processor 50, wherein the optical lens 40 is located at the front side of the camera chip and is used to collect light signals of various light sources for the camera chip; the imaging chip 10 of the camera chip is electrically connected with the processor 50 through the A / D converter. Optionally, the camera device further comprises an RGB filter 30 arranged on the general imaging area 11 of the imaging chip 10 of the camera chip. Part of the light information collected by the optical lens 40 passes through the RGB filter 30 and is converted into an electrical signal by the general imaging area 11, and then is converted into digital image data by the A / D converter 70, and the digital image data is processed into general image data by the general image processor 51 in the processor 50, for example, the general image data is compressed into image and video data in a standard format (such as MPEG4, etc.). Another part of the light information collected by the optical lens 40 passes through the F-P gradual filter 20 and is converted into an electrical signal by the spectral imaging area 12, and then is converted into digital spectral data by the A / D converter 70, and the digital spectral data is processed into spectral image data by the spectral image processor 52 in the processor 50.

[0056] Optionally, the camera device further comprises an attitude sensor 60, which is electrically connected with the processor 50 and is used to acquire attitude information of the camera device in the imaging process, and the processor 50 of the camera device is used to correct the spectral image according to the attitude information. That is, in the technical solution, not only the general imaging can provide reference for the spectral image, but also the attitude information acquired by the attitude sensor 60 can provide reference for the spectral image, and then the accurate spectral two-dimensional distribution plan of the scanned and measured object is obtained through the spectral image algorithm processing, so that the requirements for the push scanning speed and the platform attitude stability are further reduced. Optionally, the attitude sensor 60 can be a gyroscope, an acceleration sensor, a six-degree-of-freedom sensor, etc.

[0057] In addition, when the camera chip is applied to a camera device that cannot be stably scanned, such as a handheld device and a drone, if the push scanning speed of the camera device is too fast, the frame images of some wave bands cannot be obtained. At this time, part of the spectral information can be sacrificed, or the camera device is also provided with a reminding software. When the push scanning speed is greater than a preset speed, the reminding software sends a reminding prompt to remind the user to reduce the push scanning speed. Without loss of generality, the push scanning speed can be detected by using a positioning system (for example, a GPS system) built in the camera device. If the push scanning speed of the camera device is too slow, too many frame images will appear. At this time, only the required frame images need to be extracted by software, and the redundant frame images can be kicked out. In addition, if the camera device shakes during the push scanning process, resulting in a change in the target distance, etc., the automatic focusing function of the ordinary camera that the camera device usually has can be used to automatically adjust and match different frame images. In this way, the requirements for the push scanning speed and the stability of the platform attitude are reduced, thereby meeting the requirements of applying the camera chip to the camera device of the handheld device (for example, a mobile phone, a tablet computer, etc.) and a drone.

[0058] The above description is only the preferred embodiments of the present application, and does not limit the patent scope of the present application. Any equivalent structural transformation, direct / indirect application in other related technical fields, or the like made under the inventive concept of the present application, using the content of the present application specification and drawings, is included in the patent protection scope of the present application.

Claims

1. A camera chip, characterized in that, The camera chip comprises an imaging chip and an F-P gradient filter, the F-P gradient filter is integrally arranged on the surface of the imaging chip, the thickness of the F-P gradient filter gradually increases from one side to the other side, and the F-P gradient filter partially covers the surface of the imaging chip. The surface of the imaging chip partially covered by the F-P gradient filter is used as a spectral imaging area, and the rest of the surface of the imaging chip is used as a normal imaging area, the normal image obtained by the normal imaging area is used as reference information of the spectral image obtained by the spectral imaging area.

2. The camera chip of claim 1, wherein, The thickness of the F-P gradient filter linearly or stepwise increases from one side to the other side.

3. The camera chip of claim 1, wherein, The F-P gradient filter comprises a Bragg reflector or a metal film reflector.

4. The camera chip of claim 1, wherein, The thicker side of the F-P gradient filter is integrally provided with a long-pass filter on the surface away from the imaging chip, and the long-pass filter is used to filter high-order transmission peaks.

5. The camera chip of claim 4, wherein, The F-P gradient filter is formed on the surface of the imaging chip by vacuum plating, and / or the long-pass filter is formed on the surface of the thicker side of the F-P gradient filter by vacuum plating.

6. The camera chip of claim 1, wherein, The imaging chip is a black-and-white imaging chip or a color imaging chip.

7. An image pickup apparatus characterized by comprising: The camera device comprises the camera chip according to any one of claims 1 to 6.

8. The image pickup apparatus according to claim 7, wherein The camera device further comprises a posture sensor, the posture sensor is used to obtain posture information of the camera device in the imaging process, and the processor of the camera device is used to correct the spectral image according to the posture information.

9. The image pickup apparatus according to claim 7 or 8, wherein The camera device is a handheld device or a drone.

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