Large-aperture spectral analysis camera module

Abstract

The present application relates to a kind of big wide-angle spectrum analysis camera module, including lens body and object identification unit, the lens body is used to the light from the measured object is converted into the light convergence of uniform angular distribution, forms light spot after, again conversion into parallel light on imaging plane and carries out imaging, obtains the image information of light spot;The object identification unit is used to calculate RSD value by the image information of light spot, and according to RSD value, the material information of object is identified.The present application, by the light from the measured object is converted into the light convergence of uniform angular distribution, forms light spot after, again conversion into parallel light, the function of lens body is changed from object imaging into light spot imaging, can accurately receive the light of different wave bands, improve the accuracy of calculating RSD value;By corresponding RSD value and the material information of object, the material information of object can be accurately identified.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of cameras, and relates to a large-aperture spectrum analysis camera module. BACKGROUND

[0002] With the progress of the times, the digital era has been fully integrated into our lives, and the digital camera system as a modern mainstream camera tool has not only met the imaging, but also urgently needs to further expand the role of the digital camera system. Especially in life, it is necessary to develop a digital camera system that can identify specific types of objects by analyzing the spectrum of the objects and identifying the specific types of objects according to the reflected light of different objects received. SUMMARY

[0003] In view of the above problems of the prior art, the technical problem to be solved by the present application is to provide a large-aperture spectrum analysis camera module capable of identifying the types of objects.

[0004] To achieve the above-mentioned purpose, the present application provides the following technical scheme:

[0005] A large-aperture spectrum analysis camera module comprises

[0006] A lens body is used to convert the light from the measured object into uniformly distributed light, form a light spot, and then convert the light spot into parallel light on the imaging plane to form an image and obtain image information of the light spot.

[0007] An object recognition unit is used to calculate the RSD value from the image information of the light spot, and identify the material information of the object according to the RSD value.

[0008] Further, the lens body comprises a circuit board, the circuit board is provided with a base, and the base is provided with a mounting through hole; the circuit board is provided with a spectrum sensing chip at the opening of the mounting through hole, and the spectrum sensing chip is electrically connected with the circuit board; a lens barrel is connected in the mounting through hole, the lens barrel is provided with a lens, the spectrum sensing chip is provided with an imaging plane, and a filter is arranged between the lens and the imaging plane; one end of the lens barrel extends out of the mounting through hole and is connected with a diaphragm, the diaphragm is provided with a light transmission hole, and the diaphragm is provided with a light uniformity plate at the position corresponding to the light transmission hole.

[0009] The diaphragm is used to block stray light and limit the imaging range; the light uniformity plate is used to convert the light from the measured object into uniformly distributed light together with the diaphragm; the lens is used to convert the uniformly distributed light into parallel light; the filter is used for light filtering; the spectrum sensing chip is used to image the light spot on the imaging plane to obtain image information of the light spot; and the circuit board is used for data transmission and provides power supply for the spectrum sensing chip.

[0010] Further, the homogenizing sheet has a transmittance greater than or equal to 16%.

[0011] Further, the homogenizing sheet has an incident light wavelength range of 350nm-1050nm.

[0012] Further, the diaphragm has an inner diameter of the light transmission hole of 0.8mm±0.01mm.

[0013] Further, the middle part of the lens barrel is provided with an annular protrusion, the side surface of the protrusion is provided with external threads, the hole wall of the mounting through hole is provided with internal threads matched with the external threads of the side surface of the protrusion, so that the protrusion is screwed and fixed in the mounting through hole.

[0014] The upper part of the lens barrel is provided with an upper connecting part, the side surface of the upper connecting part is provided with external threads; the lower part of the diaphragm is provided with a receiving cavity, the receiving cavity is in communication with the light transmission hole; the cavity wall of the receiving cavity is provided with internal threads matched with the external threads of the side surface of the upper connecting part, so that the upper connecting part is screwed and fixed in the receiving cavity.

[0015] Further, before identifying the object, the filter with a corresponding light transmission range is selected according to the type of the measured object.

[0016] When the measured object is a human body, the filter with a light transmission range of 380nm-780nm is selected.

[0017] When the measured object is a medicine, the filter with a light transmission range of 500nm-950nm is selected.

[0018] When the measured object is food, the filter with a light transmission range of 380nm-950nm is selected.

[0019] Further, the object identification unit comprises

[0020] The RSD calculation module is configured to calculate the RSD value through the image information of the light spot and determine whether the RSD value meets the identification requirement.

[0021] The storage module is configured to store the corresponding relationship between the RSD value and the material information of the object.

[0022] The identification module is configured to query the corresponding material information of the object from the storage module according to the RSD value when the RSD value meets the identification requirement.

[0023] Further, the method for calculating the RSD value through the image information of the light spot and determining whether the RSD value meets the identification requirement comprises:

[0024] A plane rectangular coordinate system is established on the image information of the light spot with the center of the imaging plane as the origin, and a predetermined number of pixels are selected on the positive and negative directions of the X and Y axes, and the RSD values of each pixel are calculated respectively;

[0025] The calculation result is smoothed;

[0026] According to the value of the X coordinate, each pixel point is divided into a plurality of first sets, the elements of each first set are the RSD values of each pixel point with the same X coordinate value, and the mean value of the elements in each first set and the maximum difference value of the elements in the first set are calculated respectively;

[0027] According to the value of the Y coordinate, each pixel point is divided into a plurality of second sets, the elements of each second set are the RSD values of each pixel point with the same Y coordinate value, and the mean value of the elements in each second set and the maximum difference value of the elements in the second set are calculated respectively;

[0028] If the mean value of the elements of each first set and second set is less than the first RSD value, and the maximum difference value of the elements of each first set and second set is less than the second RSD value, it is judged that the RSD value meets the identification requirement; otherwise, it is judged that the RSD value does not meet the identification requirement.

[0029] Further, the predetermined number of pixels is 300 pixels, the first RSD value is 1.1, and the second RSD value is 0.3.

[0030] In the present application, the imaging area of the object is limited by the diaphragm, and the light from the measured object is converted into uniformly distributed light and then converged, and then converted into parallel light by the lens, so that the function of the lens body is changed from object imaging to light spot imaging. The spectral sensing chip can accurately receive light of different wavebands, and the accuracy of calculating the RSD value; the object recognition unit can accurately identify the material information of the object by corresponding the RSD value with the material information of the object. BRIEF DESCRIPTION OF DRAWINGS

[0031] The drawings described herein are used to provide further understanding of the present application, and form a part of the present application. The schematic embodiments of the present application and their descriptions are used to explain the present application, and do not constitute an improper limitation on the present application. In the drawings:

[0032] Figure 1 It is a structure schematic view of a preferred embodiment of the present application wide-angle spectral analysis camera module.

[0033] Figure 2 It is an exploded view of Figure 1 .

[0034] Figure 3 It is a structure block diagram of the object recognition unit.

[0035] The meanings of the various reference signs in the drawings are as follows:

[0036] Circuit board-1; Spectral sensing chip-2; Base-3; Mounting through hole-31; Filter-4; Lens barrel-5; Convex part-51; Upper connecting part-52; Lens-6; Light uniformity sheet-7; Diaphragm-8; Light transmission hole-81; Object recognition unit-9; RSD calculation module-91; Storage module-92; Recognition module-93. DETAILED DESCRIPTION

[0037] The embodiments of the present application will be described in detail below with specific specific examples, the drawings provided in the following examples only illustrate the basic concept of the present application in a schematic manner, and the following examples and features in the examples can be combined with each other without conflict.

[0038] As shown in Figure 1 and Figure 2 , a preferred embodiment of the present application wide-angle spectral analysis camera module includes a lens body and an object recognition unit 9, the lens body is used to convert the light from the measured object into uniform angular distribution of light and converge into a light spot, and then convert into parallel light on the imaging plane to image and obtain the image information of the light spot.

[0039] The lens body includes a circuit board 1, the circuit board 1 is provided with a base 3, the base 3 is provided with a mounting through hole 31, the circuit board 1 is provided with a spectral sensing chip 2 corresponding to the aperture of the mounting through hole 31, and the spectral sensing chip 2 is electrically connected with the circuit board 1. The mounting through hole 31 is connected with a lens barrel 5, the lens barrel 5 is provided with a lens 6, the spectral sensing chip 2 is provided with an imaging plane, and a filter 4 is arranged between the lens 6 and the imaging plane of the spectral sensing chip 2. One end of the lens barrel 5 extends out of the mounting through hole 31 upward and is connected with a diaphragm 8, the diaphragm 8 is provided with a light transmission hole 81, and the diaphragm 8 is provided with a light uniformity sheet 7 corresponding to the position of the light transmission hole 81. In the embodiment, the light uniformity sheet 7 is arranged between the lens 6 and the light transmission hole 81, of course, the light uniformity sheet 7 can also cover the light transmission hole 81.

[0040] Among them, the diaphragm 8 is used to block stray light and limit the imaging range. In the embodiment, the material of the diaphragm 8 is copper, and the surface is black; the inner diameter of the light transmission hole 81 of the diaphragm 8 is 0.8mm±0.01mm, which is much smaller than the inner diameter of the light transmission hole 81 of the diaphragm 8 in the normal camera module. The outer diameter of the diaphragm 8 is 5.0mm±0.01mm, and the wall thickness is 3mm±0.001mm.

[0041] The homogenizing plate 7 is used together with the diaphragm 8 to convert the light from the measured object into light with uniform angular distribution, so as to converge the light into a light spot. The homogenizing plate 7 is a 180° homogenizing plate 7, and the wavelength range of the incident light is 250nm-2500nm, and in the embodiment, the wavelength range is preferably 350nm-1050nm, that is, the homogenizing plate 7 is an ideal Lambertian body in the wavelength range of 250nm-2500nm (or 350nm-1050nm). The transmittance of the homogenizing plate 7 is greater than or equal to 16%, which is higher than that of a common homogenizing plate 7. The homogenizing plate 7 can be made of a material such as polytetrafluoroethylene, which is heat-resistant, corrosion-resistant and radiation-resistant, and is required to be suitable for long-term exposure to harsh environmental conditions. The thickness of the homogenizing plate 7 is generally 500μm.

[0042] The lens 6 is a molded aspheric lens 6, which is used to convert the light with uniform angular distribution into parallel light, so as to form a light spot with uniform light distribution on the imaging plane. The outer diameter OD of the lens 6 is generally 4.00mm, and the focal length F is generally 2.50mm. The filter 4 is used to filter out unwanted light and only keep the light in the required wavelength range, so as to improve the accuracy of identification. The spectral sensing chip 2 is used to image the light spot on the imaging plane to obtain image information of the light spot. The circuit board 1 can be a PCB board, which is used for data transmission and provides power supply for the spectral sensing chip 2.

[0043] In order to adapt to different scenes, the filter 4 can be prepared in multiple types according to the optical characteristics of the object. Before identifying the object, the filter 4 with a corresponding light transmission range is selected according to the type of the measured object. In the embodiment, three types of filters 4 are used, and the light transmission ranges of the three types of filters 4 are 380nm-780nm, 500nm-950nm and 380nm-950nm respectively.

[0044] T<0.1%@200nm-350nm&810nm-1200nm;

[0045] T>90%@380nm-780nm;

[0046] Thickness: 0.3mm.

[0047] The light transmission range of the second filter 4 is 500nm-950nm, and the specific parameters are as follows:

[0048] T<0.1%@200nm-470nm&980nm-1200nm;

[0049] T>90%@500nm-950nm;

[0050] Thickness: 0.3mm.

[0051] The third type of filter 4 has a light transmission range of 380nm to 950nm, and its specific parameters are as follows:

[0052] T<0.1%@200nm~350nm&980nm~1200nm;

[0053] T > 90% @ 380nm ~ 950nm;

[0054] Thickness: 0.3mm.

[0055] When the object being tested is a part of the human body, selecting filter 4 with a light transmission range of 380nm to 780nm allows for the identification of features such as the retina and fingerprints. When the object being tested is a medicine, selecting filter 4 with a light transmission range of 500nm to 950nm allows for the identification of the medicine's components. When the object being tested is food, selecting filter 4 with a light transmission range of 380nm to 950nm allows for the identification of the food's type.

[0056] To facilitate the replacement of the filter 4, an annular protrusion 51 is provided in the middle of the lens barrel 5. The side of the protrusion 51 is provided with external threads, and the wall of the mounting through hole 31 is provided with internal threads that match the external threads on the side of the protrusion 51. Thus, the lens barrel 5 is screwed and fixed in the mounting through hole 31 of the base 3 through the protrusion 51, and the lower end of the lens barrel 5 abuts against the filter 4. An upper connecting part 52 is provided at the upper part of the lens barrel 5. The side of the upper connecting part 52 is provided with external threads. A receiving cavity (not shown in the figure) is provided at the lower part of the aperture 8. The receiving cavity is connected to the light transmission hole 81. The wall of the receiving cavity is provided with internal threads that match the external threads on the side of the upper connecting part 52, thus, the lens barrel 5 is screwed and fixed to the aperture 8 through the upper connecting part 52, and the upper end of the upper connecting part 52 abuts against the light-diffusing plate 7. Since the aperture 8 and the lens barrel 5, as well as the lens barrel 5 and the base 3, are all screw-connected, when the filter 4 needs to be replaced, the aperture 8, the diffuser 7, the lens 6, and the lens barrel 5 can be easily removed to replace the filter 4.

[0057] like Figure 3 As shown, the object recognition unit 9 is used to calculate the RSD (relative standard deviation; the ratio of standard deviation to the arithmetic mean of the calculated result) value through the image information of the light spot, and to identify the material information of the object based on the RSD value. The object recognition unit 9 includes an RSD calculation module 91, a storage module 92, and a recognition module 93. The RSD calculation module 91, storage module 92, and recognition module 93 can be mounted on the circuit board 1, or they can be mounted separately and connected to the circuit board 1 to interact with the spectral sensing chip 2.

[0058] The RSD calculation module 91 is configured to calculate the RSD value from the image information of the light spot, and determine whether the RSD value meets the identification requirement. The calculation method of the RSD value is a prior art, and will not be described herein. The standard deviation required for the calculation can be stored in the storage module 92 in advance. The working process of the RSD calculation module 91 can include the following steps:

[0059] S1. A plane rectangular coordinate system is established on a RAW image (RAW represents unprocessed) of the light spot with the center of the imaging plane as the origin, and a predetermined number of pixels are selected on the positive and negative directions of the X and Y axes, respectively, and the RSD values of the pixels are calculated, respectively. In this embodiment, 300 pixels are selected on the positive and negative directions of the X and Y axes, respectively, for calculation.

[0060] S2. The calculation results are smoothed. The smoothing method is a prior art, and will not be described herein.

[0061] S3. According to the value of the X coordinate, each pixel point is divided into a plurality of first sets, i.e., the pixel points in the same column are divided into a first set. The elements of each first set are the RSD values of the pixel points with the same X coordinate value (i.e., in the same column), and the mean value of the elements in each first set and the maximum difference value of the elements in each first set are calculated, respectively.

[0062] S4. According to the value of the Y coordinate, each pixel point is divided into a plurality of second sets, i.e., the pixel points in the same row are divided into a second set. The elements of each second set are the RSD values of the pixel points with the same Y coordinate value (i.e., in the same row), and the mean value of the elements in each second set and the maximum difference value of the elements in each second set are calculated, respectively.

[0063] S5. If the mean value of the elements of each first set and second set is less than a first RSD value, and the maximum difference value of the elements of each first set and second set is less than a second RSD value, it is determined that the RSD value meets the identification requirement; otherwise, it is determined that the RSD value does not meet the identification requirement. In this embodiment, the first RSD value is preferably 1.1, and the second RSD value is preferably 0.3.

[0064] The storage module 92 is configured to store the corresponding relationship between the RSD value and the material information of the object. A FLASH storage chip can be used, and the data information can be stored in advance for different working environments, or can be quickly and conveniently programmed online according to the changes in requirements. The identification module 93 is configured to query the corresponding material information of the object from the storage module 92 according to the RSD value when the RSD value meets the identification requirement, and output an identification failure information when the RSD value does not meet the identification requirement.

[0065] In the embodiment, the imaging area of the object is defined by the light barrier 8, the light from the object is converged into a light spot by the homogenizing plate 7, and then the light is uniformly distributed on the imaging plane of the spectral sensing chip 2 by the lens 6, so that the spectral sensing chip 2 can accurately receive light of different wave bands, and the accuracy of calculating the RSD value is improved. The object recognition unit 9 corresponds the RSD value to the material information of the object, and can accurately identify the information of the object through the RSD value.

[0066] Finally, it should be pointed out that the above embodiments are only used to illustrate the technical solutions of the present application and are not limiting. Although the present application has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solutions of the present application can be modified or replaced by equivalents without departing from the purpose and scope of the technical solutions, and they should be covered in the scope of the claims of the present application.

Claims

1. A wide-angle spectral analysis camera module, characterized in that: The lens body is used for converting light from the measured object into light converging to form a light spot with uniform angular distribution, then converting the light converging into parallel light for imaging on an imaging plane to obtain image information of the light spot. The object recognition unit is used for calculating the RSD value from the image information of the light spot and recognizing the material information of the object according to the RSD value. The object recognition unit comprises An RSD calculation module is used for calculating the RSD value from the image information of the light spot and judging whether the RSD value meets the recognition requirement. A storage module is used for storing the corresponding relationship between the RSD value and the material information of the object. An identification module is used for querying the corresponding material information of the object from the storage module according to the RSD value when the RSD value meets the recognition requirement. The method for calculating the RSD value from the image information of the light spot and judging whether the RSD value meets the recognition requirement is as follows: A plane rectangular coordinate system is established on the image information of the light spot with the center of the imaging plane as the origin, and a predetermined number of pixels are selected on the positive and negative directions of the X and Y axes, and the RSD values of the pixels are calculated respectively; The calculation results are smoothed; According to the values of the X coordinates, the pixel points are divided into a plurality of first sets respectively, the elements of each first set are the RSD values of the pixel points with the same X coordinate value, the mean values of the elements in each first set are calculated respectively, and the maximum difference values of the elements in each first set are calculated respectively; According to the values of the Y coordinates, the pixel points are divided into a plurality of second sets respectively, the elements of each second set are the RSD values of the pixel points with the same Y coordinate value, the mean values of the elements in each second set are calculated respectively, and the maximum difference values of the elements in each second set are calculated respectively; If the mean values of the elements of each first set and second set are less than a first RSD value, and the maximum difference values of the elements of each first set and second set are less than a second RSD value, it is judged that the RSD value meets the recognition requirement; otherwise, it is judged that the RSD value does not meet the recognition requirement. The lens body comprises a circuit board, a base is arranged on the circuit board, and a mounting through hole is formed in the base; a spectrum sensing chip is arranged at the aperture of the mounting through hole corresponding to the circuit board, and the spectrum sensing chip is electrically connected with the circuit board; a lens barrel is connected in the mounting through hole, a lens is arranged in the lens barrel, an imaging plane is arranged on the spectrum sensing chip, and a filter is arranged between the lens and the imaging plane; one end of the lens barrel protrudes out of the mounting through hole upward and is connected with an aperture stop, a light transmission hole is formed in the aperture stop, and a light uniformizing plate is arranged at the position of the aperture stop corresponding to the light transmission hole; The aperture stop is used for shielding stray light and limiting the imaging range; the light uniformizing plate is used for converting the light from the measured object into light with uniform angular distribution together with the aperture stop; the lens is used for converting the light with uniform angular distribution into parallel light; the filter is used for filtering light; the spectrum sensing chip is used for imaging the light spot on the imaging plane to obtain the image information of the light spot; and the circuit board is used for data transmission and providing power supply for the spectrum sensing chip. The transmittance of the light uniformizing plate is greater than or equal to 16%.

2. The large-aperture spectral analysis camera module of claim 1, wherein: The incident light wavelength range of the light uniformizing plate is 350nm-1050nm. ​ 3. The large-aperture spectral analysis camera module of claim 2, wherein: ​ 4. The large-FOV spectral analysis camera module of claim 2, wherein: ​ 5. The large-FOV spectral analysis camera module of claim 2, wherein: The inner diameter of the light transmission hole of the diaphragm is 0.8mm±0.01mm.

6. The large-FOV spectral analysis camera module of claim 2, wherein: The middle part of the lens barrel is provided with an annular convex part, the side surface of the convex part is provided with external threads, the hole wall of the mounting through hole is provided with internal threads matched with the external threads of the side surface of the convex part, so that the convex part is screwed and fixed in the mounting through hole; The upper part of the lens barrel is provided with an upper connecting part, the side surface of the upper connecting part is provided with external threads; the lower part of the diaphragm is provided with a containing cavity, the containing cavity is communicated with the light transmission hole; the cavity wall of the containing cavity is provided with internal threads matched with the external threads of the side surface of the upper connecting part, so that the upper connecting part is screwed and fixed in the containing cavity.

7. The large-FOV spectral analysis camera module of claim 2, wherein: Before identifying the object, a filter with a corresponding light transmission range is selected according to the type of the measured object; When the measured object is a human body, a filter with a light transmission range of 380nm-780nm is selected; When the measured object is a medicine, a filter with a light transmission range of 500nm-950nm is selected; When the measured object is food, a filter with a light transmission range of 380nm-950nm is selected.

8. The large field-of-view spectral analysis camera module according to any one of claims 2 to 7, characterized in that: The predetermined number of pixels is 300 pixels, the first RSD value is 1.1, and the second RSD value is 0.3.

Images