Infrared camera device and optical module

Abstract

The invention discloses an infrared camera device and an optical module, a first surface, a second surface, a first glass substrate, a third surface, a fourth surface, a second glass plate, a third glass plate and a fifth surface are sequentially arranged from an object side to an image side along an optical axis of the infrared camera device, the first surface and the fourth surface are aspheric surfaces, the second surface is a diaphragm, and the fifth surface is a diaphragm. The third surface is a super lens surface, and the fifth surface is a chip light-sensitive surface. According to the infrared camera device, miniaturization can be realized, the integration difficulty of the device is reduced, and the development requirements of AR / VR equipment are met.

Description

Technical Field

[0001] The present application generally relates to the technical field of optical imaging equipment, and more specifically, to an infrared camera device and an optical module. Background Art

[0002] As the core support for the next generation of AR / VR interaction, eye tracking technology has shown great application potential in scenarios such as target positioning and interactive experience upgrades, and is of key significance in promoting the development of immersive interaction technology.

[0003] Currently, optical tracking is the mainstream solution for eye tracking. It illuminates the eyeball with infrared or visible light and uses a camera to capture changes in the reflected light to track eye movements. However, AR / VR devices have strict requirements for compactness. Existing eye tracking solutions use separate cameras, limited by their optical system design, which makes it difficult to miniaturize while covering the eye's full field of view. This makes device integration difficult and unsuitable for the development needs of AR / VR devices.

[0004] In view of this, there is an urgent need to provide an infrared camera device to achieve miniaturization, reduce the difficulty of device integration, and adapt to the development needs of AR / VR equipment. Summary of the Invention

[0005] In order to at least solve one or more of the technical problems mentioned above, the present application proposes a miniaturized infrared camera device in multiple aspects.

[0006] In a first aspect, the present application provides an infrared camera device, wherein along the optical axis of the infrared camera device from the object side to the image side are, in order, a first surface, a second surface, a first glass substrate, a third surface, a fourth surface, a second glass plate, a third glass plate and a fifth surface, wherein the first surface and the fourth surface are aspherical surfaces, the second surface is an aperture, the third surface is a super lens surface, and the fifth surface is a chip photosensitive surface.

[0007] In some embodiments, the focal length f2 of the second surface is greater than 0, the focal length f4 of the fourth surface is less than 0, the focal length f1 of the first surface is greater than the effective focal length f of the infrared camera device, and the focal length f3 of the third surface is less than the effective focal length f of the infrared camera device; and the focal length f1 of the first surface, the focal length f3 of the third surface, and the focal length f4 of the fourth surface satisfy the following conditions: .

[0008] In some embodiments, the curvature radius r1 of the first surface and the effective focal length f of the infrared camera device satisfy the following relationship: .

[0009] In some embodiments, the total optical path length TTL and the image height ImageH of the infrared camera device satisfy: .

[0010] In some embodiments, the focal length f3 of the third surface and the effective focal length f of the infrared camera device satisfy: .

[0011] In some embodiments, the operating wavelength range of the infrared camera device is greater than or equal to 920 nm and less than or equal to 960 nm.

[0012] In a second aspect, the present application provides an optical module, comprising: a housing; and the infrared camera device described in the first aspect and multiple embodiments, wherein the infrared camera device is installed in the housing.

[0013] Through the infrared camera device provided above, the embodiment of the present application realizes a compact arrangement of multiple optical functional surfaces along the optical axis by adopting an integrated structural design in which the first surface and the fourth surface are set as aspheric surfaces, the second surface is set as an aperture, and the third surface is set as a metalens surface, effectively compressing the axial size of the system to adapt to the spatial constraints of AR / VR devices. At the same time, with the help of the aberration compensation capability of the aspheric surface and the focusing control performance of the metalens, accurate coverage of the eye movement field and imaging clarity are guaranteed, thereby breaking through the technical bottleneck of existing eye tracking devices due to high integration difficulty caused by space limitations and difficulty in balancing miniaturization and large field of view requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The above and other objects, features and advantages of the exemplary embodiments of the present application will become readily understood by reading the detailed description below with reference to the accompanying drawings. In the accompanying drawings, several embodiments of the present application are shown in an exemplary and non-limiting manner, and the same or corresponding reference numerals represent the same or corresponding parts, wherein: Figure 1 FIG2 shows a partial structural diagram of an infrared camera device according to an optional embodiment of the present application; Figure 2 A partial structural diagram of the infrared camera device of the first embodiment is shown; Figure 3 shows an aberration diagram of the infrared imaging device of Example 1; Figure 4 The MTF of the infrared imaging device of the first embodiment is shown; Figure 5 shows a phase diagram of the infrared imaging device of Example 1; Figure 6 A partial structural diagram of an infrared camera device according to a second embodiment is shown; Figure 7shows an aberration diagram of the infrared imaging device of Example 2; Figure 8 The MTF of the infrared imaging device of the second embodiment is shown; Figure 9 shows a phase diagram of the infrared imaging device of the second embodiment; Figure 10 A partial structural diagram of an infrared camera device according to a third embodiment is shown; Figure 11 shows an aberration diagram of the infrared imaging device of Example 3; Figure 12 The MTF of the infrared imaging device of the third embodiment is shown; Figure 13 shows a phase diagram of the infrared imaging device of Example 3; Figure 14 An exemplary structural diagram of an optical module according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0015] The following will refer to the accompanying drawings and combine the embodiments to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without making creative efforts are within the scope of protection of this application.

[0016] It should be understood that the terms "include" and "comprising" used in the description and claims of this application indicate the presence of described features, wholes, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or collections thereof.

[0017] It should also be understood that the terms used in this specification are for the purpose of describing specific embodiments only and are not intended to limit this application. As used in this specification and claims, the singular forms "a," "an," and "the" are intended to include the plural forms unless the context clearly indicates otherwise. It should also be further understood that the term "and / or" as used in this specification and claims refers to any and all possible combinations of one or more of the associated listed items, including and including these combinations.

[0018] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meaning as commonly understood by ordinary technicians in the technical field to which this application belongs.

[0019] In this application, unless otherwise specified, directional words such as "up, down, top, bottom" are usually used with reference to the directions shown in the drawings, or with reference to the components themselves in the vertical, perpendicular or gravity direction; similarly, for ease of understanding and description, "inside and outside" refer to the inside and outside relative to the outline of each component itself, but the above directional words are not used to limit this application.

[0020] It should be noted that in this specification, the expressions first, second, third, etc. are only used to distinguish one feature from another feature, and do not represent any limitation on the features. Therefore, without departing from the teachings of this application, the first surface discussed below may also be referred to as the second surface or the third surface.

[0021] In the drawings, the thickness, size, and shape of the surface and substrate are slightly exaggerated for ease of illustration. Specifically, the shapes of spherical or aspherical surfaces shown in the drawings are provided by way of example. That is, the shapes of spherical or aspherical surfaces are not limited to those shown in the drawings. The drawings are for illustration only and are not drawn strictly to scale.

[0022] In this application, the object side refers to the side of the infrared camera device facing the object being photographed (not shown in the figure), and the image side refers to the side of the infrared camera device facing the imaging plane. Hereinafter, the object side of a surface or substrate refers to the side of the surface or substrate facing the object being photographed (not shown in the figure), and the image side of a surface or substrate refers to the side of the surface or substrate facing the imaging plane. In the structural diagrams shown in this application, the left side is the object side, and the right side is the image side.

[0023] The specific implementation of the present application will be described in detail below with reference to the accompanying drawings.

[0024] Figure 1 FIG. 1 shows a partial structural diagram of the infrared camera device 100 of the present application. Figure 1 As shown, along the optical axis of the infrared camera device 100 from the object side to the image side are the first surface 101, the second surface 102, the first glass substrate 103, the third surface 104, the fourth surface 105, the second glass plate 106, the third glass plate 107 and the fifth surface 108.

[0025] In the embodiment of the present application, the first surface 101 and the fourth surface 105 are even-order aspheric surfaces processed based on wafer-level optics (WLO) technology. Their surface profiles can be precisely controlled using the following even-order aspheric surface formula to specifically correct geometric aberrations such as spherical aberration, coma, and astigmatism: (1) Where Z is the distance vector height from the vertex of the aspheric surface when the aspheric surface is at a height of r along the optical axis; r represents the Y-axis coordinate value of each point on the surface; c is the reciprocal of the curvature radius r of the surface; K is the conic coefficient, is the coefficient of the additional polynomial, i.e., the aspheric higher-order term, m=2,3,4····, M is the highest number of terms in the additional polynomial.

[0026] The first surface 101, serving as the first optical interface for object-side incidence, is responsible for initially converging infrared light and compensating for on-axis aberrations, alleviating the focusing pressure of the subsequent metalens surface (i.e., the third surface 104). The fourth surface 105, located after the metalens surface, assists in compressing the system's axial dimensions (TTL) through a negative focal length design and further corrects residual aberrations in the edge field of view. Relying on the high-precision batch manufacturing characteristics of WLO technology and integrated with the glass substrate to achieve a lightweight and thin layout, the two jointly construct an aberration compensation system of "preliminary correction + fine optimization," providing the core optical support for infrared camera devices to achieve a large field of view (HFOV=102.75°) and highly uniform imaging in a compact structure.

[0027] Second surface 102 serves as an aperture. Its surrounding area can be blackened with a light-shielding coating. This physically blocks non-targeted infrared stray light from entering the subsequent optical system, effectively shielding it. The central active area of ​​second surface 102 retains its light-transmitting properties, efficiently transmitting infrared light initially focused by first surface 101 to the subsequent optical system.

[0028] The third surface 104 is a metalens surface that achieves infrared light focusing through diffraction phase control using micro-nanostructures. The surface phase distribution of the third surface 104 can be precisely designed using the following diffraction phase formula to specifically compensate for residual high-order aberrations and infrared dispersion in the first and fourth surfaces 101 and 105: (2) in, is the phase, M is the diffraction order, usually 1; are polynomial coefficients, i is the order, N is the maximum order, is the normalized radius.

[0029] Second glass plate 106 is a filter designed to match the infrared light source commonly used in eye tracking, allowing infrared light of a specific wavelength to pass through. In some implementations, the infrared camera operates at a wavelength greater than or equal to 920 nm and less than or equal to 960 nm. Therefore, second glass plate 106 allows infrared light with a wavelength greater than or equal to 920 nm and less than or equal to 960 nm to pass through.

[0030] The fifth surface 108 is the photosensitive surface of the chip, which is used to receive infrared light signals (i.e., infrared light reflected by the eyeball) focused by the optical system (aspheric surface, aperture, super lens surface, etc.), and convert the infrared light signals into electrical signals through the photosensitive layer to provide raw data for subsequent image processing (such as eye positioning and motion tracking).

[0031] The third glass plate 107 is a protective glass on the chip surface, covering the outside of the chip's photosensitive surface (i.e., the fifth surface 108). It is used to isolate the photosensitive surface from damage by external dust, moisture, mechanical scratches, etc., and ensure the structural integrity of the chip during long-term use. It is especially suitable for the high-frequency use and complex environment requirements of AR / VR devices.

[0032] The first glass substrate 103, serving as the core optical integration carrier of the infrared camera, is made of transparent glass to ensure efficient transmission of infrared light. Leveraging WLO processing technology, it integrates multiple optically functional surfaces: one side integrates the first surface 101 and the second surface 102; the other side integrates the third surface 104 and the fourth surface 105. Leveraging the high-precision batch processing capabilities of WLO technology, the first glass substrate 103 compactly integrates the spatial filtering of the aperture, the aberration correction of the aspheric surface, and the phase control of the metalens onto both sides of a single substrate. This significantly reduces the system size while providing hardware integration support for the device's large field of view (102.75°) and high-precision eye tracking through the synergistic functions of each surface.

[0033] In actual operation, the order of processing the aforementioned optical surfaces can be: first, the metalens surface (third surface 104) is processed on the image side of the first glass substrate 103, then the aperture (i.e., the second surface 102) is processed on the object side of the first glass substrate 103, and then the WLO surface (i.e., the first surface 101) is processed on the object side of the second surface 102 using the WLO technology. Finally, the WLO surface (i.e., the fourth surface 105) is processed on the image side of the third surface 104 using the WLO technology.

[0034] Combination of the above Figure 1 The infrared camera device of the present application is described. The device realizes a compact arrangement of multiple optical functional surfaces along the optical axis by adopting an integrated structural design in which the first surface and the fourth surface are set as aspheric surfaces, the second surface is set as an aperture, and the third surface is set as a metalens surface. The axial size of the system is effectively compressed to adapt to the spatial constraints of AR / VR devices. At the same time, with the help of the aberration compensation capability of the aspheric surface and the focusing control performance of the metalens, the accurate coverage of the eye movement field and the imaging clarity are guaranteed, thereby breaking through the technical bottleneck of the existing eye tracking device due to high integration difficulty caused by space limitations and difficulty in balancing miniaturization and large field of view requirements.

[0035] In the embodiment of the present application, the focal lengths of the optical surfaces of the infrared camera device 100 follow a precise collaborative design: the focal length f1 of the first surface 101 is positive and greater than the effective focal length f of the infrared camera device; the focal length f2 of the second surface 102 is greater than 0, the focal length f3 of the third surface 104 is less than the effective focal length f of the infrared camera device, and the focal length f4 of the fourth surface 105 is less than 0, and the absolute value satisfies ,at the same time .

[0036] From the perspective of optical power and functional division of labor: the third surface 104 has the smallest absolute value of focal length (the largest absolute value of optical power), and thus bears the main optical power contribution of the system. Its optical properties can significantly shorten the total axial length (TTL) of the system. Based on the lens's long focal length, the even-order aspheric surface's profile control provides core compensation for primary aberrations such as spherical aberration and coma, ensuring imaging accuracy. The positive focal length of the second surface 102 optimizes the intensity distribution and aberration transitions along the intermediate optical path, while the negative focal length of the fourth surface 105 further compresses the optical path and corrects edge aberrations. This synergistic strategy of multi-surface focal lengths in power distribution, aberration compensation, and optical path compression establishes the underlying optical design logic for compact structure and high-precision imaging.

[0037] In the embodiment of the present application, the curvature radius r1 of the first surface 101 and the effective focal length f of the infrared camera device satisfy the following relationship: , this parameter constraint can effectively control the imaging quality of the infrared camera device: by By controlling the curvature within this range, the first surface 101 can provide sufficient initial optical power to assume a partial focusing function while avoiding the introduction of high-order aberrations due to excessive curvature.

[0038] In the embodiment of the present application, the total optical path length TTL and the image height ImageH of the infrared camera device satisfy the following relationship: This proportional constraint enables the miniaturization of infrared camera designs: TTL determines the physical thickness of the infrared camera, while ImageH reflects the imaging range on the image plane, corresponding to the effective monitoring field of view required for eye tracking. This proportional constraint ensures that the system's axial length (TTL) is short enough to meet miniaturization requirements while ensuring that ImageH covers a sufficient imaging range for eye movement monitoring.

[0039] In an embodiment of the present application, the focal length f3 of the third surface and the effective focal length f of the infrared camera device satisfy the following relationship: This proportional constraint is conducive to the overall miniaturization of the infrared camera device: by Controlled within this range, the optical power of the metalens surface (inversely proportional to the focal length) precisely matches the overall optical power of the infrared camera device, ensuring that the metalens surface can perform the focusing function while avoiding the introduction of difficult-to-correct aberrations due to excessive compression of the optical path caused by a too short f3, or the increase in system axial redundancy due to an excessively long f3. This proportional constraint allows the metalens surface to focus efficiently while collaborating with other optical surfaces such as aspheric surfaces to compress the optical path, ultimately effectively reducing the total system length (TTL).

[0040] The following further describes the specific surface shapes and parameters of the infrared camera device applicable to the above-mentioned embodiments with reference to the accompanying drawings. It should be noted that the following embodiments 1 to 3 are applicable to all embodiments of the present application. Figure 1 The described features can be similarly applied to the following embodiments 1 to 3.

[0041] Example 1 Figure 2 FIG. 1 is a schematic diagram showing a partial structure of the infrared camera device 200 according to the first embodiment.

[0042] like Figure 2 As shown, along the optical axis of the infrared imaging device 200, from the object side to the image side, are the first surface 201, the second surface 202, the first glass substrate 203, the third surface 204, the fourth surface 205, the second glass plate 206, the third glass plate 207, and the fifth surface 208. The first and fourth surfaces 201 and 205 are even-order aspheric surfaces fabricated using wafer-level optics (WLO) technology. The third surface 204 is a metalens surface, and the fifth surface 208 is the chip's photosensitive surface. The second glass plate 206 is a filter, and the third glass plate 207 is a protective glass for the chip surface. Table 1 below shows the basic structural parameters of the infrared imaging device 200 of Example 1. The units for the radius of curvature and thickness / distance are all in millimeters. In Table 1, OBJ (not shown) represents the object plane, Img (not shown) represents the imaging plane, and the thickness of OBJ represents the distance from the object being photographed to the first surface 201.

[0043] Table 1

[0044] Table 2 below lists the aspheric coefficients K, A4, A6, A8, A10, A12, A14, and A16 of the aspheric surfaces (the first surface 201 and the fourth surface 205 ) that can be used in the first embodiment.

[0045] Table 2

[0046] Table 3 below gives the coefficients M, N, and normalized radius of the metalens surface (third surface 204). , polynomial coefficients A1, A2, A3, A4, A5 and A6.

[0047] Table 3

[0048] Table 4 below gives the optical parameters of the infrared camera device of Example 1, including the focal length f1 of the first surface 101, the focal length f3 of the third surface 104, the focal length f4 of the fourth surface 105, the effective focal length f of the infrared camera device, the total optical path length TTL of the infrared camera device, the image height ImageH, the horizontal field of view HFOV, the aperture number Fno, and the curvature radius r1 of the first surface.

[0049] Table 4

[0050] Table 5 below lists the values ​​of the various conditional expressions of the infrared camera device of Example 1.

[0051] Table 5

[0052] Figure 3 : shows the aberration diagram of the infrared camera device of Example 1, Figure 4 shows the modulus of the adjustment transfer function (OTF) (MTF) of the infrared camera device of the first embodiment, Figure 5 The phase diagram of the infrared imaging device of the first embodiment is shown.

[0053] exist Figure 3 In the figure, the "IMA:xxx mm" above each sub-figure represents the image height. The sub-figures are arranged from smallest to largest IMA, covering the entire field of view, to verify the aberration performance of the infrared camera device throughout the entire eye movement process. Specifically, the different curves in each sub-figure represent different infrared wavelengths, such as 920nm, 930nm, 940nm, 950nm, and 960nm. The closer the curves are, the smaller the focus deviation at each wavelength. The curves in each sub-figure are generally smooth, with small fluctuations, indicating that the aberration distribution of the infrared camera device in Example 1 is stable across a large field of view (102.75°).

[0054] exist Figure 4 In the figure, the solid line represents the T direction of the field of view, and the dotted line represents the S direction of the field of view. Different solid lines and dotted lines correspond to different fields of view. The closer the curves in the T direction and the S direction are, the more consistent the imaging quality in the T direction and the S direction is. Therefore, regardless of whether the eyeball moves up and down or left and right, the contrast restoration ability of details such as its contour and boundary is basically the same, which means that the astigmatism of the infrared camera device is extremely low. At the same time, Figure 4The area enclosed under each curve is relatively large, which indicates that the infrared camera device can not only clearly restore coarse details (such as pupil contour) but also retain certain details (such as iris texture), that is, the imaging quality of the infrared camera device is balanced in the entire spatial frequency range.

[0055] exist Figure 5 In the image, the phase diagram shows no distortion or breakage from center to edge, demonstrating minimal wavefront distortion in the infrared camera. Furthermore, the spacing between the rings is essentially uniform, indicating uniform wavefront quality across the entire field of view. Consequently, even when the eye moves to the edge of the field of view, wavefront distortion remains minimal, maintaining image clarity consistent with the center.

[0056] according to Figures 3 to 5 It can be seen that the curves are balanced, and the aberration, MTF and phase are well controlled. In other words, the infrared camera device provided in the first embodiment can achieve good imaging quality.

[0057] Example 2 Figure 6 FIG. 1 is a schematic diagram showing a partial structure of an infrared camera device 600 according to a second embodiment.

[0058] like Figure 6 As shown, along the optical axis of the infrared imaging device 600, from the object side to the image side, are the first surface 601, the second surface 602, the first glass substrate 603, the third surface 604, the fourth surface 605, the second glass plate 606, the third glass plate 607, and the fifth surface 608. The first and fourth surfaces 601 and 605 are even-order aspheric surfaces fabricated using wafer-level optics (WLO) technology. The third surface 604 is the metalens surface, and the fifth surface 608 is the chip's photosensitive surface. The second glass plate 606 is the filter, and the third glass plate 607 is the chip's protective glass. Table 6 below shows the basic structural parameters of the infrared imaging device 600 of Example 2. The units for the radius of curvature and thickness / distance are all in millimeters. In Table 6, OBJ (not shown) represents the object plane, Img (not shown) represents the imaging plane, and the thickness of OBJ represents the distance from the object being photographed to the first surface 601.

[0059] Table 6

[0060] Table 7 below lists the aspheric coefficients K, A4, A6, A8, A10, A12, A14, and A16 of each aspheric surface (the first surface 601 and the fourth surface 605 ) that can be used in the second embodiment.

[0061] Table 7

[0062] Table 8 below gives the coefficients M, N, and normalized radius of the metalens surface (third surface 404). , polynomial coefficients A1, A2, A3, A4, A5 and A6.

[0063] Table 8

[0064] The following Table 9 gives the optical parameters of the infrared camera device of Example 2, including the focal length f1 of the first surface 601, the focal length f3 of the third surface 604, the focal length f4 of the fourth surface 605, the effective focal length f of the infrared camera device, the total optical path length TTL of the infrared camera device, the image height ImageH, the horizontal field of view HFOV, the aperture number Fno, and the curvature radius r1 of the first surface.

[0065] Table 9

[0066] Table 10 below lists the values ​​of the various conditional expressions of the infrared camera device of Example 2.

[0067] Table 10

[0068] Figure 7 : shows the aberration diagram of the infrared camera device of Example 2, Figure 8 The MTF of the infrared camera device of the second embodiment is shown. Figure 9 The phase diagram of the infrared imaging device of the second embodiment is shown.

[0069] exist Figure 7 In the figure, the "IMA:xxx mm" above each sub-figure represents the image height. The sub-figures are arranged from smallest to largest IMA, covering the entire field of view, to verify the aberration performance of the infrared camera device throughout the entire eye movement process. Specifically, the different curves in each sub-figure represent different infrared wavelengths, such as 920nm, 930nm, 940nm, 950nm, and 960nm. The closer the curves are, the smaller the focus deviation at each wavelength. The curves in each sub-figure are generally smooth, with small fluctuations, indicating that the aberration distribution of the infrared camera device of Example 2 is stable within the field of view (90.21°).

[0070] exist Figure 8 In the figure, the solid line represents the T direction of the field of view, and the dotted line represents the S direction of the field of view. Different solid lines and dotted lines correspond to different fields of view. The closer the curves in the T direction and the S direction are, the more consistent the imaging quality in the T direction and the S direction is. Therefore, regardless of whether the eyeball moves up and down or left and right, the contrast restoration ability of details such as its contour and boundary is basically the same, which means that the astigmatism of the infrared camera device is extremely low. At the same time, Figure 8The area enclosed under each curve is relatively large, which indicates that the infrared camera device can not only clearly restore coarse details (such as pupil contour) but also retain certain details (such as iris texture), that is, the imaging quality of the infrared camera device is balanced in the entire spatial frequency range.

[0071] exist Figure 9 In the image, the phase diagram shows no distortion or breakage from center to edge, demonstrating minimal wavefront distortion in the infrared camera. Furthermore, the spacing between the rings is essentially uniform, indicating uniform wavefront quality across the entire field of view. Consequently, even when the eye moves to the edge of the field of view, wavefront distortion remains minimal, maintaining image clarity consistent with the center.

[0072] according to Figures 7 to 9 It can be seen that the curves are balanced, and the aberration, MTF and phase are well controlled. In other words, the infrared camera device provided in the second embodiment can achieve good imaging quality.

[0073] Example 3 Figure 10 FIG. 1 is a schematic diagram showing a partial structure of an infrared camera device 1000 according to a third embodiment.

[0074] like Figure 10 As shown, along the optical axis of the infrared imaging device 1000, from the object side to the image side, are the first surface 1001, the second surface 1002, the first glass substrate 1003, the third surface 1004, the fourth surface 1005, the second glass plate 1006, the third glass plate 1007, and the fifth surface 1008. The first and fourth surfaces 1001 and 1005 are even-order aspheric surfaces fabricated using wafer-level optics (WLO) technology. The third surface 1004 is a metalens surface, and the fifth surface 1008 is the chip's photosensitive surface. The second glass plate 1006 is a filter, and the third glass plate 1007 is a protective glass for the chip surface. Table 11 below shows the basic structural parameters of the infrared imaging device 1000 of Example 3. The units for the radius of curvature and thickness / distance are all in millimeters. In Table 6, OBJ (not shown) represents the object plane, Img (not shown) represents the imaging plane, and the thickness of OBJ represents the distance from the object being photographed to the first surface 1001.

[0075] Table 11

[0076] Table 12 below lists the aspheric coefficients K, A4, A6, A8, A10, A12, A14, and A16 of the aspheric surfaces (the first surface 1001 and the fourth surface 1005 ) that can be used in Example 3.

[0077] Table 12

[0078] Table 13 below gives the coefficients M, N, and normalized radius of the metalens surface (third surface 1004). , polynomial coefficients A1, A2, A3, A4, A5 and A6.

[0079] Table 13

[0080] The following Table 14 gives the optical parameters of the infrared camera device of Example 3, including the focal length f1 of the first surface 1001, the focal length f3 of the third surface 1004, the focal length f4 of the fourth surface 1005, the effective focal length f of the infrared camera device, the total optical path length TTL of the infrared camera device, the image height ImageH, the horizontal field of view HFOV, the aperture number Fno, and the curvature radius r1 of the first surface.

[0081] Table 14

[0082] Table 15 below lists the values ​​of the various conditional expressions of the infrared camera device of Example 3.

[0083] Table 15

[0084] Figure 11 : shows the aberration diagram of the infrared camera device of Example 3, Figure 12 The MTF of the infrared camera device of the third embodiment is shown. Figure 13 The phase diagram of the infrared imaging device of the third embodiment is shown.

[0085] exist Figure 11 In the figure, the IMA:xxx mm above each sub-figure represents the image height. The sub-figures are arranged from smallest to largest IMA, covering the entire field of view, to verify the aberration performance of the infrared camera device throughout the entire eye movement process. Specifically, the different curves in each sub-figure represent different infrared wavelengths, such as 920nm, 930nm, 940nm, 950nm, and 960nm. The closer the curves are, the smaller the focus deviation at each wavelength. In each sub-figure, the curves are generally smooth, with small fluctuations, indicating that the aberration distribution of the infrared camera device of Example 3 is stable within the field of view (140.75°).

[0086] exist Figure 12 In the figure, the solid line represents the T direction of the field of view, and the dotted line represents the S direction of the field of view. Different solid lines and dotted lines correspond to different fields of view. The closer the curves in the T direction and the S direction are, the more consistent the imaging quality in the T direction and the S direction is. Therefore, regardless of whether the eyeball moves up and down or left and right, the contrast restoration ability of details such as its contour and boundary is basically the same, which means that the astigmatism of the infrared camera device is extremely low. At the same time, Figure 12The area enclosed under each curve is relatively large, which indicates that the infrared camera device can not only clearly restore coarse details (such as pupil contour) but also retain certain details (such as iris texture), that is, the imaging quality of the infrared camera device is balanced in the entire spatial frequency range.

[0087] exist Figure 13 In the image, the phase diagram shows no distortion or breakage from center to edge, demonstrating minimal wavefront distortion in the infrared camera. Furthermore, the spacing between the rings is essentially uniform, indicating uniform wavefront quality across the entire field of view. Consequently, even when the eye moves to the edge of the field of view, wavefront distortion remains minimal, maintaining image clarity consistent with the center.

[0088] according to Figures 11 to 13 It can be seen that the curves are balanced, and the aberration, MTF and phase are well controlled. In other words, the infrared camera device provided in the third embodiment can achieve good imaging quality.

[0089] Those skilled in the art should understand that the above-mentioned infrared lens can be combined with one or more housings and other necessary components to form an optical module, so that the infrared lens provided in this application can be used in electronic devices and smart terminals.

[0090] Accordingly, if Figure 14 As shown, the present application proposes an optical module 1400 , which includes a housing 1401 and an infrared camera device 1402 , wherein the infrared camera device 1402 is accommodated in the housing 1401 .

[0091] The housing 1401 has a light window 1403 , which allows light to pass through and corresponds to the infrared camera device 1402 .

[0092] In summary, the infrared lens and optical module according to the embodiments of the present application are explained. By adopting an integrated structural design in which the first and fourth surfaces are aspherical, the second surface is an aperture, and the third surface is a metalens surface, a compact arrangement of multiple optical functional surfaces is achieved along the optical axis, effectively compressing the axial size of the system to adapt to the spatial constraints of AR / VR devices. At the same time, by leveraging the aberration compensation capability of the aspheric surface and the focus control performance of the metalens, accurate coverage of the eye movement field of view and imaging clarity are guaranteed, thereby overcoming the technical bottleneck of existing eye tracking devices due to high integration difficulty caused by space limitations and difficulty in balancing miniaturization and large field of view requirements.

[0093] Although multiple embodiments of the present application have been shown and described herein, it will be apparent to those skilled in the art that such embodiments are provided by way of example only. Those skilled in the art can conceive of many changes, modifications, and alternatives without departing from the thought and spirit of the present application. It should be understood that in the process of practicing the present application, various alternatives to the embodiments of the present application described herein can be adopted. The accompanying claims are intended to define the scope of protection of the present application and therefore cover equivalents or alternatives within the scope of these claims.

Claims

1. An infrared camera device, characterized in that: Along the optical axis of the infrared camera device, from the object side to the image side, there are the first surface, the second surface, the first glass substrate, the third surface, the fourth surface, the second glass plate, the third glass plate and the fifth surface, wherein the first surface and the fourth surface are aspherical surfaces, the second surface is an aperture, the third surface is a super lens surface, and the fifth surface is a chip photosensitive surface.

2. The infrared camera device according to claim 1, wherein: The focal length f2 of the second surface is greater than 0, the focal length f4 of the fourth surface is less than 0, the focal length f1 of the first surface is greater than the effective focal length f of the infrared camera device, and the focal length f3 of the third surface is less than the effective focal length f of the infrared camera device; as well as The focal length f1 of the first surface, the focal length f3 of the third surface, and the focal length f4 of the fourth surface satisfy: .

3. The infrared camera device according to claim 1, wherein: The curvature radius r1 of the first surface and the effective focal length f of the infrared camera device satisfy the following relationship: .

4. The infrared camera device according to claim 1, wherein: The total optical path length TTL and image height ImageH of the infrared camera device satisfy the following relationship: .

5. The infrared camera device according to claim 1, wherein: The focal length f3 of the third surface and the effective focal length f of the infrared camera device satisfy the following relationship: .

6. The infrared camera device according to claim 1, wherein: The operating wavelength range of the infrared camera device is greater than or equal to 920 nm and less than or equal to 960 nm.

7. An optical module, characterized in that: include: case; and The infrared camera device according to any one of claims 1 to 6, wherein the infrared camera device is installed in the housing.

Images