Optical system and detection method thereof

Abstract

The invention discloses an optical system and a detection method thereof. The optical system comprises a component to be detected and a detector. The to-be-detected component comprises a lens and a first optical film material, at least one surface of the lens is a non-plane, and the first optical film material is arranged on the non-plane; the detector is located on the light emitting side of the to-be-detected component and is configured to detect the characteristics of the light which passes through the to-be-detected component and is emitted. The optical system further comprises a light receiving component which is located between the component to be detected and the detector, and the light receiving component is configured to converge light rays which pass through the edge area of the component to be detected and are emitted to the detector basically in parallel, so that the detector detects the characteristics of the light rays which pass through the edge area of the component to be detected and are emitted. The light receiving part is arranged between the to-be-detected part and the detector, so that the light rays emitted from the edge area of the to-be-detected part can be collected and emitted to the detector, and the characteristics of the light rays emitted from all positions of the to-be-detected part can be measured and analyzed.

Description

Technical Field

[0001] The present disclosure relates to an optical system and a detection method thereof. Background Art

[0002] The technologies used in virtual reality products include Fresnel lenses and ultra-short-focus folded optical paths (Pancake). Pancake greatly reduces the required distance between near-eye display devices and human eyes by folding the optical path, making VR devices lighter and thinner. The lens surface of virtual reality products using Pancake is attached with a reflective polarizing film and a 1 / 4 wave plate. The light passes through the reflective polarizing film and the 1 / 4 wave plate in turn to form circularly polarized light. At present. Generally, the quality is guaranteed by aligning the circular deflection of the light emitted from the center area of ​​the lens attached with the above-mentioned film layer. Summary of the invention

[0003] Embodiments of the present disclosure provide an optical system and a detection method.

[0004] The embodiment of the present disclosure provides an optical system, comprising: a component to be detected and a detector. The component to be detected comprises a lens and a first optical film material, at least one surface of the lens is a non-plane, and the first optical film material is arranged on the non-plane; the detector is located on the light-emitting side of the component to be detected, and is configured to detect the characteristics of the light passing through the component to be detected and emitted. The optical system also includes a light-collecting component, which is located between the component to be detected and the detector, and the light-collecting component is configured to converge the light passing through the edge area of ​​the component to be detected and emitted and emit it to the detector in substantially parallel, so that the detector detects the characteristics of the light passing through the edge area of ​​the component to be detected and emitted.

[0005] For example, according to an embodiment of the present disclosure, the light collecting component includes a light focusing structure and a collimating structure, and the light focusing structure is located between the collimating structure and the component to be detected.

[0006] For example, according to an embodiment of the present disclosure, the light collecting component further includes a first light shaping structure, which is located between the collimating structure and the focusing structure and is configured to perform divergent shaping on the light before it is incident on the collimating structure.

[0007] For example, according to an embodiment of the present disclosure, the optical structure further includes: a second light shaping structure, located at the light incident side of the component to be detected. The second light shaping structure is configured to adjust the deflection angle of the light incident on the component to be detected so that the light incident on different positions of the first optical film material is substantially perpendicular to the first optical film material.

[0008] For example, according to an embodiment of the present disclosure, the first optical film material includes a phase delay film, and the detector is also configured to obtain at least one of the extension direction of the optical axis of the phase delay film and the phase delay amount of the light passing through the phase delay film according to the characteristics of the emitted light.

[0009] For example, according to an embodiment of the present disclosure, the component to be inspected further includes a second optical film material, the second optical film material is located on the non-plane and on the light incident side of the phase delay film, and the second optical film material includes a reflective polarizing film.

[0010] For example, according to an embodiment of the present disclosure, the light receiving component includes an optical axis, and the light receiving component is configured to converge light within an angle θ emitted from the component to be detected, where θ does not exceed 70 degrees.

[0011] For example, according to an embodiment of the present disclosure, the optical system further includes: a light source located at the light incident side of the component to be detected. The light source is configured to emit parallel light rays.

[0012] For example, according to an embodiment of the present disclosure, the focusing structure includes a biconvex lens, the collimating structure includes a plano-convex lens, and the first light shaping structure includes a plano-concave lens.

[0013] For example, according to an embodiment of the present disclosure, the non-plane includes at least one of an aspherical surface and a spherical surface.

[0014] The present disclosure provides a detection method for the above-mentioned optical system, comprising: selecting a reference component, wherein the reference component comprises a lens and a reference optical film material, the lens comprises at least one curved surface, the lens has the same thickness as the lens, and the curved surface has the same parameters as the non-plane, the reference optical film material is arranged on the curved surface, and the light collecting component is located between the reference component and the detector; using the detector to detect a first polarization characteristic of light passing through an edge area of ​​the reference component and emitting, wherein the first polarization characteristic comprises a first elliptical polarization light parameter; compensating a Mueller matrix component in the first elliptical polarization light parameter so that the first polarization characteristic comprises a first circularly polarized light parameter; replacing the reference component with the component to be detected; using the detector to detect a second polarization characteristic of light passing through an edge area of ​​the component to be detected and emitting, wherein the second polarization characteristic comprises a second elliptical polarization light parameter; and comparing the second elliptical polarization light parameter with the first circularly polarized light parameter.

[0015] For example, according to an embodiment of the present disclosure, the detection method also includes: using the detector to detect a third polarization characteristic of the light that passes through the central area of ​​the reference component and emerges, wherein the third polarization characteristic includes a second circularly polarized light parameter; using the detector to detect a fourth polarization characteristic of the light that passes through the central area of ​​the component to be detected and emerges, wherein the fourth polarization characteristic is the same as the third polarization characteristic.

[0016] For example, according to an embodiment of the present disclosure, the reference optical film material includes a first phase delay film and a first reflective polarizing film, the first reflective polarizing film and the first phase delay film are both located on the curved surface, and the first reflective polarizing film is located on the light incident side of the first phase delay film; compensating for the Mueller matrix component in the first elliptically polarized light parameter includes: the compensation amount for the Mueller matrix component of the first phase delay film is f(Δθ), and the f(Δθ) is related to at least one of the curvature of the curved surface and the refractive index of the lens.

[0017] For example, according to an embodiment of the present disclosure, the first optical film material includes a second phase delay film, the component to be detected also includes a second optical film material, the second optical film material is located on the non-plane and on the light incident side of the first optical film material, the second optical film material includes a second reflective polarizing film, and the detection method further includes: according to the comparison result of the second elliptically polarized light parameters with the first circularly polarized light parameters, rotating at least one of the second phase delay film and the second reflective polarizing film to complete the optical alignment at the edge area of ​​the component to be detected.

[0018] For example, according to an embodiment of the present disclosure, the first optical film material includes a second phase delay film; based on the comparison result of the second elliptically polarized light parameters and the first circularly polarized light parameters, at least one of the optical axis extension direction of the second phase delay film and the phase delay amount of light passing through the second phase delay film is detected. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings of the embodiments will be briefly introduced below. Obviously, the drawings in the following description only relate to some embodiments of the present disclosure, but are not intended to limit the present disclosure.

[0020] Figure 1 A schematic diagram of the local structure of an optical system and the polarization state of light passing through the optical system.

[0021] Figure 2 For light to pass through Figure 1 Schematic diagram of the polarization state during the reflective polarizing film and phase delay film process.

[0022] Figure 3 It is a schematic diagram of the cross-sectional structure of an optical system provided according to an embodiment of the present disclosure.

[0023] Figure 4 A cross-sectional view of an optical system provided according to an example of an embodiment of the present disclosure.

[0024] Figure 5 for Figure 4 Simulation diagram of the optical system shown.

[0025] Figure 6 A cross-sectional view of an optical system provided according to another example of an embodiment of the present disclosure.

[0026] Figure 7 A cross-sectional view of an optical system provided according to another example of an embodiment of the present disclosure.

[0027] Figure 8 A detection method for an optical system is provided according to an embodiment of the present disclosure.

[0028] Fig. 9 Schematic diagram of the polarization state of light after compensation of the reference optical film material. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solution and advantages of the embodiments of the present disclosure clearer, the technical solution of the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings of the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, rather than all of the embodiments. Based on the described embodiments of the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0030] Unless otherwise defined, the technical terms or scientific terms used in the present disclosure should be understood by people with ordinary skills in the field to which the present disclosure belongs. The words "first", "second" and similar words used in the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. The words "include" or "comprise" and similar words mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects.

[0031] Figure 1 A schematic diagram of the local structure of an optical system and the polarization state of light passing through the optical system. Figure 2 For light to pass through Figure 1 Schematic diagram of the polarization state during the reflective polarizing film and phase delay film process.

[0032] like Figure 1 and Figure 2 As shown, the optical system includes an optical structure and a detector 19 located on the light-emitting side of the optical structure. The optical structure includes a lens 11 and a reflective polarizing film 12 and a phase delay film 13 located on both sides of the lens 11. For example, the phase delay film 13 can be a 1 / 4 wave plate. Both sides of the lens 11 are curved surfaces, and the reflective polarizing film 12 and the phase delay film 13 are both arranged on the curved surfaces. Parallel light 14 is irradiated on the lens 11. The propagation direction of the linear polarized light 17 emitted from the central area of ​​the reflective polarizing film 12 is parallel to the optical axis of the lens 11, and the propagation direction of the linear polarized light 18 emitted from the edge area of ​​the reflective polarizing film 12 is at an angle θ to the optical axis of the lens 11. The linear polarized light 17 emits circularly polarized light 16 after passing through the central area of ​​the phase delay film 13, and the linear polarized light 18 emits elliptically polarized light 15 after passing through the edge area of ​​the phase delay film 13. The detector 19 on the light-emitting side of the phase delay film 13 is used to detect the characteristics of the circularly polarized light 16 emitted from the central area of ​​the phase delay film 13.

[0033] During the study, the inventors of the present application found that: on the one hand, due to the refractive properties of lenses, parallel light rays will have a deviation angle after being incident on the lens, causing the light emitted from the lens to be diverged, and unable to collect light for the entire lens aperture, so that the light emitted from the edge area of ​​the lens cannot be detected by the detector. Therefore, the optical active positioning of the optical film material on the lens can only perform alignment of the center point; on the other hand, when a phase delay film is affixed to the curved surface of the lens, the phase delay film needs to be stretched, and the stretching will cause the optical axis of the phase delay film to change. Therefore, the polarization state of the polarized light emitted from the edge area of ​​the phase delay film may become an elliptical polarization state. The elliptical polarization state light is located outside the center point and cannot be measured and analyzed by the detector for optical properties.

[0034] The present disclosure provides an optical system and a detection method thereof. The optical system includes a component to be detected and a detector. The component to be detected includes a lens and a first optical film material, at least one surface of the lens is a non-plane, and the first optical film material is arranged on the non-plane; the detector is located on the light-emitting side of the component to be detected, and is configured to detect the characteristics of the light passing through the component to be detected and emitted. The optical system also includes a light-collecting component, which is located between the component to be detected and the detector, and the light-collecting component is configured to converge the light passing through the edge area of ​​the component to be detected and emitted and emit it to the detector in substantially parallel, so that the detector detects the characteristics of the light passing through the edge area of ​​the component to be detected and emitted.

[0035] In the optical system provided by the present invention, by arranging a light collecting component between the component to be detected and the detector, the light emitted from the edge area of ​​the component to be detected can be collected and directed to the detector, and the detector can comprehensively detect the characteristics of the light emitted from various positions of the component to be detected, so as to realize the measurement and analysis of the characteristics of the light emitted from various positions of the component to be detected, and realize the optical alignment of the center point of the optical film material and positions other than the center point.

[0036] The detection method applied to the above optical system includes: selecting a reference component; using a detector to detect the first polarization characteristic of light passing through the edge area of ​​the reference component and emitting, the first polarization characteristic including the first elliptical polarization light parameter; compensating the Mueller matrix component in the first elliptical polarization light parameter so that the first polarization characteristic includes the first circular polarization light parameter; replacing the reference component with the component to be detected; using a detector to detect the second polarization characteristic of light passing through the edge area of ​​the component to be detected and emitting, the second polarization characteristic including the second elliptical polarization light parameter; comparing the second elliptical polarization light parameter with the first circular polarization light parameter. The reference component includes a lens and a reference optical film material, the lens includes at least one curved surface, the lens has the same thickness as the lens, and the curved surface has the same parameters as the non-plane surface, the reference optical film material is arranged on the curved surface, and the light collecting component is located between the reference component and the detector.

[0037] The detection method of the optical system provided by the present invention, on the basis of converging the light emitted from the edge area of ​​the reference component and the component to be detected through the light collecting component and emitting them in parallel to the detector, compensates the Mueller matrix component in the first elliptically polarized light parameter so that the first polarization characteristic includes the first circularly polarized light parameter, so as to adjust the characteristic parameter reference of the light emitted from the edge area of ​​the reference component to the circularly polarized light parameter, facilitates the analysis of the second elliptically polarized light parameter of the light emitted from the edge area of ​​the component to be detected to determine the change of the optical performance of the first optical film material, can provide feedback on the production process of the first optical film material, and can also optimize the edge point alignment of the first optical film material with other optical film materials in the optical active alignment process.

[0038] The optical system and detection method thereof provided by the embodiments of the present disclosure are described below in conjunction with the accompanying drawings.

[0039] Figure 3 It is a schematic diagram of the cross-sectional structure of an optical system provided according to an embodiment of the present disclosure.

[0040] like Figure 3As shown, the optical system includes a component to be detected 100 and a detector 200. The component to be detected 100 includes a lens 110 and a first optical film material 120, at least one surface 111 of the lens 110 is a non-plane 1110, and the first optical film material 120 is disposed on the non-plane 1110. For example, the first optical film material 120 disposed on the non-plane 1110 is also formed into a curved surface shape, such as the first optical film material 120 can be conformal to the non-plane 1110. For example, the first optical film material 120 can be attached to the non-plane 1110. For example, the lens 110 can be a lens.

[0041] Figure 3 The number of lenses 110 is schematically shown as one. For example, if it is a single lens, the lens 110 includes two surfaces 111, both surfaces 111 are non-planes 1110, and the first optical film material 120 is arranged on the non-plane 1110 where the light-emitting surface of the lens 110 is located. However, it is not limited thereto, the number of lenses can be multiple, the surfaces of the lenses can be three, four or more, the non-planes included in the lenses can be one, two, three or more, and the first optical film material is arranged on one of the non-planes. For example, the above-mentioned non-plane 1110 can refer to a curved surface.

[0042] In some examples, such as Figure 3 As shown, the non-plane surface 1110 of the lens 110 includes at least one of an aspherical surface and a spherical surface. For example, the lens 110 includes a plurality of non-plane surfaces 1110, all of which may be aspherical surfaces, or all of which may be spherical surfaces, or some of the non-plane surfaces 1110 may be aspherical surfaces, and some of the non-plane surfaces 1110 may be spherical surfaces. Of course, the embodiments of the present disclosure are not limited thereto, and the non-plane surface may be a free-form surface.

[0043] like Figure 3 As shown, the detector 200 is located at the light-emitting side of the component to be inspected 100 , and is configured to detect the characteristics of the light that passes through the component to be inspected 100 and emerges.

[0044] For example, the detector 200 may include a polarization analyzer (PSA), which can detect the size of the incident polarized light in a specific polarization state component, and obtain the polarization properties of the light, such as the Stokes vector, by calculation. For example, the detector 200 may also include a charge coupled device (CCD). For example, the CCD (cannot receive polarization information, but can only receive light intensity information. During the measurement, at least four independent polarization analyses can be performed. Since the Stokes vector has four components, it is necessary to measure the light intensity of at least four projection components during polarization analysis to obtain the Stokes vector of a beam of light. In this way, by measuring the outgoing polarization state after illumination with polarized light of multiple different polarization states, the Mueller matrix in the Stokes vector can be calculated.

[0045] For example, Figure 3As shown, the light 011 incident on the component to be inspected 100 is parallel light. For example, the light 012 emitted from the component to be inspected 100 is divergent light.

[0046] like Figure 3 As shown, the optical system further includes a light collecting component 300, which is located between the component to be detected 100 and the detector 200. The light collecting component 300 is configured to converge the light rays that pass through the edge area of ​​the component to be detected 100 and emit, and emit them substantially in parallel to the detector 200, so that the detector 200 detects the characteristics of the light rays that pass through the edge area of ​​the component to be detected 100 and emit. The above-mentioned “substantially parallel” may include that all the light rays are emitted completely in parallel to the detector, or that more than 90% of all the light rays are emitted in parallel to the detector.

[0047] Relative to Figure 1 In the optical system shown, when the light emitted by the component to be detected is directly directed toward the detector, the detector cannot detect the light emitted from the edge area of ​​the component to be detected. In the optical system provided by the present invention, by setting a light collecting component between the component to be detected and the detector, the light emitted from the edge area of ​​the component to be detected can be collected and directed toward the detector in parallel. The detector can comprehensively detect the characteristics of the light emitted from various positions of the component to be detected, so as to realize the measurement of the characteristics of the light emitted from various positions of the component to be detected, and further realize the optical alignment of the center point of the optical film material and positions other than the center point.

[0048] The above-mentioned component to be detected includes a central area and an edge area, and the central area may refer to an area surrounding the center of the component to be detected. For example, the central area may be an area with a radius of z millimeters with the center of the non-plane as the center, such as z may be 2, and the value of z may be determined by the curvature of the lens; the edge area may refer to a circle area surrounding the central area.

[0049] Figure 3 The diagram schematically shows the light incident on the central area and edge area of ​​the component to be detected. During the detection process, the light incident on the central area and the light incident on the edge area of ​​the component to be detected can be incident in different time periods to enable the detector to respectively detect the characteristics of the polarized light emitted from the central area and edge area of ​​the component to be detected.

[0050] For example, Figure 3As shown, the component to be detected 100 may be at least a partial structure of an optical structure using an ultra-short focus folded optical path (Pancake). For example, the optical structure using an ultra-short focus folded optical path (Pancake) includes a lens 110, a transflective film, a phase delay film, a reflective polarizing film, and a linear polarizing film arranged on the surface of the lens 110. For example, along the direction parallel to the optical axis of the lens 110, the transflective film, the phase delay film, the reflective polarizing film, and the linear polarizing film are arranged in sequence, and when the optical structure is applied to a near-eye display device, the display screen is located on the side of the transflective film away from the phase delay film.

[0051] For example, the principle of the folded optical path is as follows: a wave plate can be provided on the light-emitting side of the display screen located on one side of the lens, and the image light emitted from the display screen is converted into right-handed circularly polarized light after passing through the wave plate, and the polarization state of the right-handed circularly polarized light remains unchanged after passing through the transflective film. The right-handed circularly polarized light is transmitted through the lens and reaches the phase delay film, and the right-handed circularly polarized light incident on the phase delay film is converted into p-linear polarized light, and the p-linear polarized light is reflected back to the phase delay film by the reflective polarizing film, where the first reflection occurs. Then, the p-linear polarized light is converted into right-handed circularly polarized light after passing through the phase delay film, and the right-handed circularly polarized light is transmitted through the lens and reaches the transflective film, and is reflected at the transflective film, where the second reflection occurs. Due to half-wave loss, the reflected light changes from right-handed circularly polarized light to left-handed circularly polarized light. The left-handed circularly polarized light is transmitted through the lens and reaches the phase delay film, and the left-handed circularly polarized light is converted into s-linear polarized light through the phase delay film, and then the s-linear polarized light is transmitted through the reflective polarizing film and the linear polarizing film and then emitted to the human eye.

[0052] In some examples, such as Figure 3 As shown, the first optical film material 120 includes a phase delay film 120, and the detector is configured to obtain at least one of the extension direction of the optical axis of the phase delay film 120 and the phase delay amount of the light passing through the phase delay film 120 according to the characteristics of the emitted light. For example, the detector 200 can detect the change of the optical axis of the phase delay film 120 and the phase delay amount of a specific wavelength calculated according to the characteristics of the light emitted through the component to be detected.

[0053] For example, Figure 3 As shown, the phase delay film 120 is configured to enable the transmitted light to achieve conversion between a circular polarization state and a linear polarization state. For example, the phase delay film 120 can be a 1 / 4 wave plate. For example, the phase delay film 120 includes a birefringent material, for example, the material of the phase delay film 120 can include a liquid crystal polymer or a polycarbonate. For example, the phase delay film 120 has the following characteristics: there is a direction with the lowest refractive index and a direction with the highest refractive index in the plane of the film layer, which are the fast axis and the slow axis respectively, and the phase of the polarized light parallel to the slow axis after passing through the phase delay film 120 is delayed by 1 / 4 wavelength compared with the polarized light parallel to the fast axis after passing through the phase delay film 120.

[0054] When the phase delay film is attached to the non-planar surface of the lens, such as the curved surface, the phase delay film is stretched, which affects its phase delay characteristics. For example, the stretching of the phase delay film will affect its birefringence characteristics, thereby affecting the change in the polarization state of the light in the folded optical path (Pancake). For example, the light that should be circularly polarized light emitted through the edge of the phase delay film becomes elliptically polarized light. Figure 2 shown.

[0055] In some examples, such as Figure 3 As shown, the component to be detected 100 further includes a second optical film material 130, which is located on a non-planar surface and on the light incident side of the phase delay film 120, and the second optical film material 130 includes a reflective polarizing film 130. For example, the lens 100 includes two non-planar surfaces, and the phase delay film 120 and the reflective polarizing film 130 are respectively located on two different non-planar surfaces.

[0056] For example, Figure 3 As shown, the functions of the reflective polarizing film 130 are as follows: there is a light transmission axis direction in the plane of the film layer, the transmittance of the polarization component of the incident light parallel to the light transmission axis direction (such as s-linear polarized light) is greater than the transmittance of the polarization component perpendicular to the light transmission axis direction (such as p-linear polarized light), and the reflectivity of the polarization component parallel to the light transmission axis direction (such as s-linear polarized light) is less than the reflectivity of the polarization component perpendicular to the light transmission axis direction (such as p-linear polarized light). For example, the reflective polarizing film can also be called a polarization beam splitting film. For example, the transmittance of polarized light parallel to the light transmission axis direction of the reflective polarizing film is not less than 85%, such as not less than 90%, such as not less than 95%, such as not less than 98%; the reflectivity of polarized light perpendicular to the light transmission axis direction of the reflective polarizing film is not less than 85%, such as not less than 90%, such as not less than 95%, such as not less than 98%. For example, the reflective polarizing film can include a reflective polarizing brightening film (dual brightness enhancement film, DBEF), a cholesteric phase-based liquid crystal polymer film, and the like.

[0057] For example, Figure 3 As shown, the angle between the slow axis of the phase retarder film 120 and the light transmission axis of the reflective polarizing film 130 is 45 degrees, so that the linear polarized light is converted into circular polarized light after passing through the reflective polarizing film and the phase retarder film.

[0058] For example, the transflective film in the above-mentioned folded optical path (Pancake) is configured to transmit part of the light and reflect another part of the light. For example, the transflective film may include at least one film layer, such as the thickness of each film layer may be 10 to 200 nanometers. For example, the transmittance of the transflective film may be 50%, and the reflectivity may be 50%. For example, the transmittance of the transflective film may be 60%, and the reflectivity may be 40%. For example, the transmittance of the transflective film may be 65%, and the reflectivity may be 35%. For example, the light transmission axis of the linear polarization film in the above-mentioned folded optical path (Pancake) coincides with the light transmission axis of the reflective polarization film 130, such as the linear polarization film may be a linear polarization film, which is used to further filter other stray light and only allow polarized light (such as s-linear polarized light) passing through the linear polarization film to enter the human eye. For example, the material of the linear polarization film may include polyvinyl alcohol (PVA) with added dichroic molecules, liquid crystal polymer film with added dichroic molecules, etc.

[0059] Of course, the embodiments of the present disclosure are not limited thereto, and the component to be detected may also be other structures, such as a structure in which a circular polarization film is provided on the curved surface of the lens, or a structure in which only a quarter wave plate is provided on the curved surface of the lens.

[0060] Figure 4 A cross-sectional view of an optical system provided according to an example of an embodiment of the present disclosure.

[0061] In some examples, such as Figure 4 As shown, the light collecting component 300 includes a light collecting structure 310 and a collimating structure 320, and the light collecting structure 310 is located between the collimating structure 320 and the component to be detected 100. For example, the light collecting structure 310 is configured to collect the light passing through the edge area of ​​the component to be detected 100 and emitted in a direction close to the center area. For example, the collimating structure 320 is configured to collimate the light passing through the component to be detected 100 and the light collecting structure 310 to emit light so that the light incident on the detector 200 is parallel light.

[0062] For example, Figure 4 As described, the focusing structure 310 may include a first lens group, and the collimating structure 320 may include a second lens group. For example, the first lens group includes at least one convex lens, such as a biconvex lens, a plano-convex lens, or a concave-convex lens. For example, the second lens group includes at least one convex lens, such as a biconvex lens, a plano-convex lens, or a concave-convex lens. For example, the first lens group may also include other lenses, such as a concave lens. For example, the second lens group may also include other lenses, such as a concave lens. For example, the number of lenses included in the first lens group and the second lens group may be the same or different.

[0063] In some examples, such as Figure 4As shown, the light collecting component 300 also includes a first light shaping structure 330, which is located between the collimating structure 310 and the focusing structure 320, and is configured to diverge and shape the light before it is incident on the collimating structure 320. For example, the first light shaping structure 330 is configured to diverge the light that passes through the focusing structure 320 and emerges, and the diverged light is collimated into parallel light by the collimating structure 310 and then incident on the detector 200. For example, the first light shaping structure 330 may include a third lens group. For example, the third lens group includes at least one concave lens, such as a biconcave lens, a plano-concave lens, or a convex-concave lens. For example, the third lens group may also include other lenses, such as a convex lens. For example, the number of lenses included in the third lens group may be the same as or different from the number of at least one of the first lens group and the second lens group.

[0064] In some examples, such as Figure 4 As shown, the focusing structure 310 includes a biconvex lens, the collimating structure 320 includes a plano-convex lens, and the first light shaping structure 330 includes a plano-concave lens. For example, the plane of the plano-convex lens is arranged opposite to the plane of the plano-concave lens, and all the light emitted from the plano-concave lens is incident on the plano-convex lens. For example, all the light emitted from the biconvex lens is incident on the plano-concave lens.

[0065] In some examples, such as Figure 3 and Figure 4 As shown, the light receiving component 300 includes an optical axis, and the light receiving component 300 is configured to converge the light within an angle θ emitted from the component to be detected 100, and θ does not exceed 70 degrees. For example, the optical axis of the light receiving component 300 extends along the X direction, and the maximum angle between the light 012 and the optical axis of the light receiving component 300 is θ, such as the maximum angle between the light 012 and the optical axis of the light receiving component 300 does not exceed 70 degrees. For example, the maximum angle between the light 012 and the optical axis of the light receiving component 300 does not exceed 65 degrees. For example, the maximum angle between the light 012 and the optical axis of the light receiving component 300 does not exceed 60 degrees. For example, the maximum angle between the light 012 and the optical axis of the light receiving component 300 does not exceed 55 degrees. For example, the maximum angle between the light 012 and the optical axis of the light receiving component 300 does not exceed 50 degrees. For example, the maximum angle between the light 012 and the optical axis of the light receiving component 300 does not exceed 45 degrees. For example, the maximum angle between the light 012 and the optical axis of the light receiving component 300 does not exceed 40 degrees. For example, the maximum angle between the light 012 and the optical axis of the light receiving component 300 does not exceed 35 degrees. For example, the maximum angle between the light 012 and the optical axis of the light receiving component 300 does not exceed 30 degrees. For example, the maximum angle between the light 012 and the optical axis of the light receiving component 300 does not exceed 25 degrees. For example, the maximum angle between the light 012 and the optical axis of the light receiving component 300 does not exceed 20 degrees. For example, the maximum angle between the light 012 and the optical axis of the light receiving component 300 does not exceed 15 degrees.

[0066] The light-collecting component provided in the optical system provided by the present invention can converge light rays at a larger angle emitted from the edge area of ​​the component to be detected, so as to improve the detector's detection of the characteristics of the light rays emitted from the edge area of ​​the component to be detected, and realize the detection of the light rays emitted from various positions of the component to be detected.

[0067] Figure 5 for Figure 4 Simulation diagram of the optical system shown.

[0068] For example, Figure 5 As shown, parallel light passes through the component to be detected 100 and emits divergent light, and the light receiving component 300 converges the divergent light and emits parallel light to the detector 200. The light receiving component has a good focusing effect, and the light emitted from the component to be detected changes its deflection direction through the light receiving component, so that all the light is incident on the detector in parallel, which is conducive to the subsequent detection of the optical properties of the first optical film material.

[0069] Figure 6 A cross-sectional view of an optical system provided according to another example of an embodiment of the present disclosure. Figure 6 The optical system shown is Figure 4 The optical system shown is different in that it further comprises a light source 500 .

[0070] In some examples, such as Figure 5 As shown, the light source 500 is located at the light incident side of the component to be detected 100, and the light source 500 is configured to emit parallel light. For example, the light source 500 may include a polarization state generator (PSG) so that the light incident on the component to be detected 100 is polarized light, such as circularly polarized light. For example, the light source 500 may emit light in the visible light band.

[0071] Figure 7 A cross-sectional view of an optical system provided according to another example of an embodiment of the present disclosure. Figure 7 The optical system shown is Figure 4 The difference of the optical system shown is that the optical system further comprises a second light shaping structure 400 .

[0072] In some examples, such as Figure 7 As shown, the second light shaping structure 400 is located at the light incident side of the component to be inspected 100. For example, Figure 7 The optical system shown may include Figure 6 As shown in the light source, the second light shaping structure 400 is located between the light source and the component to be detected 100. For example, the light incident on the second light shaping structure 400 may be parallel light.

[0073] In some examples, such as Figure 7As shown, the second light shaping structure 400 is configured to adjust the deflection angle of the light incident on the component to be detected 100 so that the light incident on different positions of the first optical film material 120 is substantially perpendicular to the first optical film material 120. The above-mentioned “the light incident on different positions of the first optical film material 120 is substantially perpendicular to the first optical film material 120” includes that the light incident on different positions of the first optical film material 120 is completely perpendicular to the surface of the first optical film material 120 close to the lens 110, or that more than 90% of the light incident on different positions of the first optical film material 120 is perpendicular to the surface of the first optical film material 120 close to the lens 110.

[0074] By setting a second light shaping structure on the light-emitting side of the component to be detected to adjust the light to be basically vertically incident on the first optical film material, the local position optical axis direction and phase delay of the phase delay film can be adjusted, so that the light emitted from the edge of the component to be detected is basically still circularly polarized light, which is beneficial to improving the optical performance of the component to be detected.

[0075] For example, Figure 7 As shown, the second light shaping structure 400 may include a fourth lens group. For example, the fourth lens group includes at least one convex lens, such as a biconvex lens, a plano-convex lens, or a concave-convex lens. For example, the fourth lens group may also include other lenses, such as a concave lens.

[0076] For example, Figure 7 As shown, the second light shaping structure 400 may include a biconvex lens, and the second light shaping structure 400 is configured to diverge the light incident on the component to be inspected 100 .

[0077] Figure 8 According to an embodiment of the present disclosure, a method for applying to the above Figure 7 Methods for detecting optical systems other than those shown in the figure. Figure 8 As shown, the detection method includes the following steps S01-S06.

[0078] Step S01: Select a reference component.

[0079] The reference component includes a lens and a reference optical film material, the lens includes at least one curved surface, the lens of the reference component has the same thickness as the lens of the component to be detected, and the curved surface of the lens has the same parameters as the non-plane surface of the lens, the reference optical film material is arranged on the curved surface, and the light collecting component is located between the reference component and the detector. For example, the curved surface of the lens and the non-plane surface of the lens can have the same surface shape. For example, the curvature of the curved surface of the lens can be the same as the curvature of the non-plane surface of the lens.

[0080] In some examples, the reference optical film material includes a first phase retardation film and a first reflective polarization film, both of which are located on the curved surface, and the first reflective polarization film is located on the light incident side of the first phase retardation film. For example, linear polarization light is converted into circular polarization light after passing through the first reflective polarization film and the first phase retardation film.

[0081] For example, the first reflective polarizing film in the reference optical film material can be Figure 4 The second optical film material 130 in the component to be inspected 100 has the same features as those in the reference optical film material 100, which will not be described in detail. Figure 4 The phase delay film 120 in the component to be inspected 100 shown has the same features, which will not be described in detail here.

[0082] Of course, the embodiments of the present disclosure are not limited thereto, and the reference optical film material may also only include a circular polarization film disposed on the curved surface of the lens.

[0083] Step S02: using a detector to detect the first polarization characteristic of the light that passes through the edge area of ​​the reference component and emerges.

[0084] The first polarization characteristic includes a first elliptically polarized light parameter.

[0085] In some examples, the detection method further includes using a detector to detect a third polarization characteristic of light that passes through the central area of ​​the reference component and emerges, and the third polarization characteristic includes a second circularly polarized light parameter. For example, the light that passes through the central area of ​​the reference component and emerges may be circularly polarized light. For example, the light source may be a laser, and by moving the light source to illuminate the central area and edge area of ​​the reference component respectively, the detector can detect the light that emerges from the central area of ​​the reference component and the light that emerges from the edge area of ​​the reference component, and the detector analyzes the polarization characteristics.

[0086] For example, the first elliptically polarized light parameter includes the Stokes vector.

[0087] For example, the polarization state of light can be changed by changing the amplitude, phase, and polarization rate of light. When polarized light passes through optical elements, such as reflective polarizing films, phase retardation films, etc., the polarization state of light can be represented by a linear combination of four Stokes parameters. For example, the Stokes parameters of linear polarized light in the horizontal and vertical directions are [1±1 0 0], the Stokes parameters of linear polarized light in the ±45 degree direction are [1 0±1 0], the Stokes parameters of right-handed circularly polarized light are [1 0 0 1], and the Stokes parameters of left-handed circularly polarized light are [1 0 0 -1]. The matrix form of the Stokes vector is as follows:

[0088]

[0089] The above matrix represents the conversion capability of the optical element to change the polarization state between the incident light and the outgoing light, wherein M represents the Mueller matrix, and the Mueller matrix can be used to estimate the capability of the optical element to change the polarization state of light.

[0090] For example, when there are multiple optical elements in the optical path, the Stokes parameters of the outgoing light after passing through the multiple optical elements can be a linear combination of the incident light and the Stokes parameters of each optical element, which can be expressed by matrix multiplication as S0=M n ···M2·M1·S1.

[0091] For example, the Stokes parameters of the first phase retardation film can be represented by the following matrix M1:

[0092]

[0093] The above δ represents the azimuth angle of the optical axis direction with respect to the X-axis of the ellipsometer, and the above θ represents the phase delay amount.

[0094] For example, the Stokes parameters of the first reflective polarizing film can be represented by the following matrix M2:

[0095]

[0096] Above Indicates the rotation angle.

[0097] Therefore, the incident light passes through the reference optical film material and then emits light that satisfies S0=M2·M1·S1.

[0098] Step S03: compensating the Mueller matrix component in the first elliptically polarized light parameter so that the first polarization characteristic includes the first circularly polarized light parameter.

[0099] In some examples, compensating the Mueller matrix component in the first elliptically polarized light parameter includes compensating the Mueller matrix component of the first phase delay film by an amount of f(Δθ), where f(Δθ) is related to at least one of the curvature of the curved surface of the lens and the refractive index of the lens. For example, f(Δθ) is related to the thickness of the lens. For example, f(Δθ) is related to the distance between the incident point of the light incident on the curved surface of the lens and the optical axis.

[0100] For example, the Mueller matrix component m of the first phase retardation film can be 11 、m 12 、m 13 、m 21 、m 22 、m 23 、m 31 、m 32 、m 33 Make compensation.

[0101] For example, the matrix M1' after compensating the azimuth angle δ in the Mueller matrix component of the first phase retardation film by f(Δθ) is expressed as follows:

[0102]

[0103] For example, substituting the above compensated matrix M1' into S0, we obtain S0 = M2·M1'·S1, where M2·M1'·S1 is expressed as follows:

[0104]

[0105] The resulting S0 is expressed as follows:

[0106]

[0107] It can be seen that the light emitted after compensating the azimuth angle δ in the Mueller matrix component of the first phase delay film includes the first circularly polarized light parameter, such as the right-handed circularly polarized light parameter. Compensating the parameters of the light emitted from the edge of the reference component can be regarded as calibrating the parameters, and the first circularly polarized light parameter is used as the reference parameter for subsequent detection of other components to be detected. For example, the Mueller matrix parameters of the light emitted from each position in the edge area can be compensated, or only the Mueller matrix parameters of the light in the partial area of ​​the edge area that is far away from the central area can be compensated.

[0108] For example, Figure 4 As shown, the parallel light emitted from the collimating structure 320 is incident on the polarization analyzer in the detector 200, which is beneficial to reducing the error caused by the non-collimated light after receiving the light irradiating the detector during Mueller decomposition.

[0109] For example, the detector can be connected to the processing unit to compensate for the Mueller matrix component of the first phase delay film. For example, the processing unit can be a central processing unit (CPU), a digital signal processor (DSP), or other forms of processing units with data processing capabilities and / or program execution capabilities, such as a field programmable gate array (FPGA), etc.; for example, the central processing unit (CPU) can be an X86 or ARM architecture, etc. For example, the processing unit can implement the control function with a software algorithm so that it can be executed by various types of processors. For example, considering the level of existing hardware technology, the processing unit can be a module implemented with a software algorithm.

[0110] Fig. 9 Schematic diagram of the polarization state of light after compensation of the reference optical film material.

[0111] For example, Fig. 9As shown, the reference optical film material includes a first phase delay film 001 and a first reflective polarizing film 002. Both the first reflective polarizing film 002 and the first phase delay film 001 are curved, and a lens between the first reflective polarizing film 002 and the first phase delay film 001 is not shown.

[0112] For example, Fig. 9 As shown, the light incident on the first reflective polarizing film 002 may be natural light 003, which is converted into linearly polarized light 004 after passing through the first reflective polarizing film 002, and which is converted into circularly polarized light 005 after passing through the first phase delay film 001. Fig. 9 It can be seen that after the Mueller matrix of the first phase delay film 001 is compensated, the light 005 emitted from the edge area of ​​the reference optical film material is circularly polarized light, and no longer Figure 2 Elliptically polarized light is shown.

[0113] Step S04: Replace the reference component with the component to be inspected.

[0114] In some examples, the component to be detected is the component to be detected in the above embodiment, such as the component to be detected includes Figures 3 to 6 The first optical film material 120 shown in the figure includes a second phase delay film (ie, the phase delay film 120 in the above embodiment), and the component to be detected also includes Figures 3 to 6 The second optical film material 130 shown includes a second reflective polarizing film (ie, the reflective polarizing film 130 in the above embodiment). The second optical film material is located on the non-plane and on the light incident side of the first optical film material.

[0115] Step S05: using a detector to detect the second polarization characteristic of the light that passes through the edge area of ​​the component to be detected and emerges.

[0116] The second polarization characteristic includes a second elliptically polarized light parameter.

[0117] In some examples, the detection method further includes: using a detector to detect a fourth polarization characteristic of light that passes through the central area of ​​the component to be detected and emerges, the fourth polarization characteristic being the same as the third polarization characteristic. For example, the light source may be a laser, and the light source may be moved to irradiate light passing through the central area and the edge area of ​​the component to be detected, respectively, and the detector may detect both the light emitted from the central area of ​​the component to be detected and the light emitted from the edge area of ​​the component to be detected, and the polarization characteristics are analyzed by the detector.

[0118] For example, the light that passes through the central area of ​​the component to be inspected and emerges may be circularly polarized light.

[0119] Step S06: Compare the second elliptically polarized light parameter with the first circularly polarized light parameter.

[0120] The parameters of the elliptically polarized light emitted from the edge of the reference component are algorithmically compensated to obtain the first circularly polarized light parameters as the reference parameters. By comparing the second elliptically polarized light parameters of the component to be inspected with the reference parameters, the difference between the second elliptically polarized light parameters and the reference parameters can be obtained.

[0121] From the direction close to the center area to the direction away from the center area, the greater the angle of deflection of the light after entering the edge area of ​​the lens and incident on the first phase delay film on the curved surface of the lens, the greater the degree of deviation of the light emitted from the first phase delay film from the circular polarization state; by performing algorithmic compensation on the parameters of the light emitted from the edge of the reference component, the reference parameters of the light emitted from the edge of the reference component can be adjusted to the parameters of the circularly polarized light, which is convenient for analyzing the second elliptically polarized light parameters of the light emitted from the edge area of ​​the component to be inspected to determine the change in the optical properties of the first optical film material, which can not only provide feedback on the production process of the first optical film material, but also optimize the edge point alignment of the first optical film material with other optical film materials during the optical active alignment process.

[0122] In some examples, the detection method further includes: rotating at least one of the second phase delay film and the second reflective polarization film to complete optical alignment at the edge area of ​​the component to be detected based on the comparison result of the second elliptically polarized light parameters with the first circularly polarized light parameters.

[0123] By comparing the difference between the second elliptically polarized light parameters and the reference parameters, the angular error between the second phase delay film and the second reflective polarizing film can be obtained. Therefore, optical active alignment can be completed by rotating, for example, the second reflective polarizing film so that the angle between the second phase delay film and the second reflective polarizing film is 45 degrees.

[0124] In some examples, the detection method further includes: detecting at least one of an optical axis extension direction of the second phase delay film and a phase delay amount of light passing through the second phase delay film according to a comparison result of the second elliptically polarized light parameter and the first circularly polarized light parameter.

[0125] By comparing the difference between the second elliptically polarized light parameters and the reference parameters, at least one of the offset of the optical axis and the phase delay of the second phase delay film can be obtained, thereby providing feedback on the subsequent tensile strength and pressure when the second phase delay film is bonded to the lens, the softness of the second phase delay film in the process, the selection of materials, etc., so as to improve the optical properties of the formed component to be inspected.

[0126] There are a few points to note:

[0127] (1) In the drawings of the embodiments of the present disclosure, only the structures related to the embodiments of the present disclosure are involved, and other structures can refer to the general design.

[0128] (2) In the absence of conflict, features in the same embodiment or in different embodiments of the present disclosure may be combined with each other.

[0129] The above description is merely an exemplary embodiment of the present disclosure and is not intended to limit the protection scope of the present disclosure. The protection scope of the present disclosure is determined by the appended claims.

Claims

1. An optical system, comprising: The component to be detected includes a lens and a first optical film material, at least one surface of the lens is a non-plane, and the first optical film material is arranged on the non-plane; A detector is located at the light-emitting side of the component to be detected and is configured to detect the characteristics of the light that passes through the component to be detected and emits. Wherein, the optical system also includes a light collecting component, which is located between the component to be detected and the detector, and the light collecting component is configured to converge the light passing through the edge area of ​​the component to be detected and emitted and emit it basically in parallel to the detector, so that the detector can detect the characteristics of the light passing through the edge area of ​​the component to be detected and emitted.

2. The optical system according to claim 1, wherein: The light collecting component comprises a light collecting structure and a collimating structure, and the light collecting structure is located between the collimating structure and the component to be detected.

3. The optical system according to claim 2, wherein: The light collecting component further includes a first light shaping structure, which is located between the collimating structure and the focusing structure and is configured to perform divergent shaping on the light before it is incident on the collimating structure.

4. The optical system according to any one of claims 1 to 3, further comprising: The second light shaping structure is located at the light incident side of the component to be detected, The second light shaping structure is configured to adjust the deflection angle of the light incident on the component to be inspected so that the light incident on different positions of the first optical film material is substantially perpendicular to the first optical film material.

5. The optical system according to claim 1, wherein: The first optical film material includes a phase delay film, and the detector is further configured to obtain at least one of an extension direction of an optical axis of the phase delay film and a phase delay amount of the light passing through the phase delay film according to the characteristics of the emitted light.

6. The optical system according to claim 5, wherein: The component to be detected further includes a second optical film material, the second optical film material is located on the non-plane and on the light incident side of the phase delay film, and the second optical film material includes a reflective polarizing film.

7. The optical system according to any one of claims 1 to 3, wherein: The light receiving component comprises an optical axis, and the light receiving component is configured to converge light within an angle θ emitted from the component to be detected, where θ does not exceed 70 degrees.

8. The optical system according to any one of claims 1 to 3, further comprising: A light source is located at the light incident side of the component to be detected, Wherein, the light source is configured to emit parallel light rays.

9. The optical system according to claim 3, wherein: The focusing structure includes a biconvex lens, the collimating structure includes a plano-convex lens, and the first light shaping structure includes a plano-concave lens.

10. The optical system according to any one of claims 1 to 3, wherein: The non-planar surface includes at least one of an aspherical surface and a spherical surface.

11. A detection method for an optical system according to any one of claims 1 to 3, comprising: Selecting a reference component, wherein the reference component includes a lens and a reference optical film material, the lens includes at least one curved surface, the lens has the same thickness as the lens, and the curved surface has the same parameters as the non-plane surface, the reference optical film material is arranged on the curved surface, and the light collecting component is located between the reference component and the detector; Using the detector to detect a first polarization characteristic of light that passes through an edge region of the reference component and emerges, wherein the first polarization characteristic includes a first elliptically polarized light parameter; Compensating the Mueller matrix component in the first elliptically polarized light parameter so that the first polarization characteristic includes a first circularly polarized light parameter; replacing the reference component with the component to be detected; The detector is used to detect the second polarization characteristic of the light that passes through the edge area of ​​the component to be detected and emerges, wherein the second polarization characteristic includes a second elliptically polarized light parameter; The second elliptically polarized light parameter is compared with the first circularly polarized light parameter.

12. The detection method according to claim 11, further comprising: The detector is used to detect the third polarization characteristic of the light that passes through the central area of ​​the reference component and emerges, wherein the third polarization characteristic includes a second circularly polarized light parameter; The detector is used to detect a fourth polarization characteristic of light that passes through the central area of ​​the component to be detected and emerges, wherein the fourth polarization characteristic is the same as the third polarization characteristic.

13. The detection method according to claim 11, wherein: The reference optical film material comprises a first phase delay film and a first reflective polarizing film, wherein the first reflective polarizing film and the first phase delay film are both located on the surface of the curved surface, and the first reflective polarizing film is located on the light incident side of the first phase delay film; Compensating the Mueller matrix component in the first elliptically polarized light parameter includes: the compensation amount of the Mueller matrix component of the first phase delay film is f(Δθ), and the f(Δθ) is related to at least one of the curvature of the curved surface and the refractive index of the lens.

14. The detection method according to claim 13, wherein: The first optical film material includes a second phase delay film, the component to be detected also includes a second optical film material, the second optical film material is located on the non-plane and on the light incident side of the first optical film material, and the second optical film material includes a second reflective polarizing film, The detection method also includes: according to the comparison result of the second elliptically polarized light parameter and the first circularly polarized light parameter, rotating at least one of the second phase delay film and the second reflective polarizing film to complete the optical alignment at the edge area of ​​the component to be detected.

15. The detection method according to claim 11, wherein: The first optical film material includes a second phase retardation film; At least one of the extending direction of the optical axis of the second phase retardation film and the phase retardation amount of the light passing through the second phase retardation film is detected according to the comparison result of the second elliptically polarized light parameter and the first circularly polarized light parameter.

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