Transmittance test equipment

Abstract

The present invention relates to a transmittance test device, comprising a light source and a stage located at the light emitting side of the light source, the stage being provided with a carrying surface for carrying a sample, and a light conversion structure being provided between the light source and the carrying surface for converting the light emitted by the light source into circularly polarized light. By providing the light conversion structure, the light emitted by the light source is converted into circularly polarized light, the influence of the polarization characteristics of the light is eliminated, and the accuracy of the transmittance test is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of transmittance testing, and in particular to a transmittance testing device. Background Art

[0002] The commonly used FDC transmittance test equipment in the industry is VMS-1S, whose light source has a certain degree of polarization. Since the camera hole area of ​​FDC is affixed with POL (polarizer), when testing products with polarizers, the placement direction of the sample and the accuracy of the POL's own application will affect the accuracy of the transmittance test. Summary of the invention

[0003] In order to solve the above technical problems, the present invention provides a transmittance testing device to solve the influence of the polarization characteristics of the light source on the transmittance test.

[0004] In order to achieve the above-mentioned purpose, the technical solution adopted in an embodiment of the present invention is: a transmittance testing device, comprising a light source and a stage located on the light output side of the light source, the stage being provided with a carrying surface for carrying samples, and a light conversion structure being provided between the light source and the carrying surface for converting the light emitted by the light source into circularly polarized light.

[0005] Optionally, along the emitting direction of the light source, the light conversion structure includes a first transparent substrate, a polarizing film layer, a complex refractive film layer and a second transparent substrate stacked in sequence, the polarizing film layer is used to convert the light emitted by the light source into linear polarized light, and the complex refractive film layer is used to convert the linear polarized light into circularly polarized light.

[0006] Optionally, the angle between the stretching direction of the complex refractive film layer and the transmission axis of the polarizing film layer is ±45°±15°.

[0007] Optionally, the phase difference value of the complex refraction film layer is 5000nm-10000nm.

[0008] Optionally, the material of the complex-refracting film layer is polyethylene terephthalate or super complex-refracting polyester film.

[0009] Optionally, the first transparent substrate and the polarizing film layer are connected by a pressure-sensitive adhesive, the polarizing film layer and the complex refracting film layer are connected by a pressure-sensitive adhesive, and the complex refracting film layer and the second transparent substrate are connected by a pressure-sensitive adhesive.

[0010] Optionally, a first groove is formed in the first area of ​​the stage, the first groove extends in a direction from the supporting surface toward the light source, a first light hole is formed at the bottom of the first groove, and the light conversion structure is accommodated in the first groove.

[0011] Optionally, a cross-sectional shape of the groove in the light emitting direction of the light source is an inverted trapezoid.

[0012] Optionally, a mounting portion for mounting the light source is included, a second light through hole is provided on the mounting portion, and a receiving portion for receiving the light conversion structure is provided on the light exit side of the second light through hole:

[0013] The accommodating portion is provided with a second groove, the light conversion structure is accommodated in the second groove, the accommodating portion includes a first surface facing the stage, and the second groove is extended in a direction from the first surface to the second light hole;

[0014] The accommodating portion further includes a third groove, which extends from the bottom of the second groove toward the light source and passes through the accommodating portion, and a cross-sectional area of ​​an end of the third groove away from the second groove is greater than or equal to an area of ​​the second light-transmitting hole.

[0015] Optionally, in the light emitting direction of the light source, the cross-sectional shape of the second groove is an inverted trapezoid.

[0016] Optionally, the mounting portion and the accommodating portion are integrated into an integral structure.

[0017] The beneficial effect of the present invention is that: through the arrangement of the light conversion structure, the light emitted by the light source is converted into circularly polarized light, the influence of the polarization characteristics of the light is eliminated, and the accuracy of the transmittance test is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A schematic diagram showing the transmittance of polarizers placed at different rotation angles in the related art;

[0019] Figure 2 A schematic diagram showing the principle that the light emitted by a light source has polarization characteristics;

[0020] Figure 3 A schematic diagram showing a light conversion structure in an embodiment of the present invention;

[0021] Figure 4 A schematic diagram showing the transmittance of light of different polarization states of a transmittance test device without a light conversion structure;

[0022] Figure 5 A schematic diagram showing light transmittance at different polarization states of a transmittance test device after a light conversion structure is set;

[0023] Figure 6 A schematic diagram showing the transmittance of light without the light conversion structure;

[0024] Figure 7A schematic diagram showing light transmittance of a light conversion structure;

[0025] Figure 8 Schematic diagram showing light transmittance of complex refractive film layers with different phase difference values;

[0026] Fig. 9 It is a schematic diagram of the refractive index of the phase difference film in various directions;

[0027] Fig.10 Schematic diagram of the transmittance test equipment structure Figure 1 ;

[0028] Fig.11 A schematic diagram of the structure of the stage is shown;

[0029] Fig.12 Schematic diagram of the transmittance test equipment structure Figure 2 ;

[0030] Fig.13 A schematic diagram showing the partial structure of the transmittance test equipment. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings of the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all of the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0032] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0033] When testing the transmittance of the FDC (under-screen camera) of the GC-D8, it was found that the transmittance data changed significantly when the orientation of the panel was changed. Further testing using only the analyzer (polarizer) found that the transmittance differed significantly when the polarizer was rotated at different angles, such as Figure 1Curve 100 represents the transmittance of the polarizer when it is rotated 0 degrees, curve 200 represents the transmittance of the polarizer when it is rotated 45 degrees, and curve 300 represents the transmittance of the polarizer when it is rotated 90 degrees. Therefore, it is confirmed that the light emitted by the light source has polarization characteristics.

[0034] The principle of polarization of light emitted by a light source is as follows Figure 2 As shown. A halogen lamp is used as the light source. The light emitted is non-polarized light. However, a lens (made of glass) is designed on it for collimation. When the light passes through the lens, it produces polarization characteristics. The Fresnel formula is as follows:

[0035]

[0036] Among them, A p1 is the vibration amplitude of the incident light in the P direction, A′ p1 is the vibration amplitude of the reflected light in the P direction, A s1 is the vibration amplitude of the incident light in the S direction, A′ s1 is the vibration amplitude of the reflected light in the S direction, A p2 is the vibration amplitude of the refracted light in the P direction, A s2 is the vibration amplitude of the refracted light in the S direction.

[0037] When light waves pass through the interface of different media, reflection and refraction will occur, and the incident light is divided into two parts: reflected light and refracted light. Although the relationship between the directions of these two beams of light can be determined by the laws of reflection and refraction, the amplitude and vibration orientation of the two beams cannot be determined. Based on the assumption that light is a transverse wave, Fresnel divided the incident light into linearly polarized light with a vibration plane parallel to the incident plane and linearly polarized light perpendicular to the incident plane, and derived the Fresnel formula for the relationship between the refraction ratio and the reflection ratio of light.

[0038] Since the specific polarization state of the partially polarized light generated in this way cannot be determined (it may contain linear polarization, elliptically polarized light, and circularly polarized light with different polarization directions), when testing products with POL (polarizer) such as FDC and fingerprint holes, the transmittance is affected by the sample placement and POL application accuracy, and the true transmittance data cannot be obtained.

[0039] In response to the above problems, the present embodiment provides a transmittance testing device, including a light source and a stage located on the light output side of the light source, the stage being provided with a carrying surface for carrying samples, and a light conversion structure being provided between the light source and the carrying surface for converting the light emitted by the light source into circularly polarized light.

[0040] Figure 4 It indicates the transmittance of light of different polarization states after passing through the panel with polarizer without setting the light conversion structure. Figure 5It indicates that the light conversion structure is set up, and the transmittance of light in different polarization states after passing through the panel with the polarizer. It can be seen that after converting the light emitted by the light source into circularly polarized light, the limitation of linearly polarized light can be broken and the transmittance can be improved.

[0041] Figure 6 A light transmittance curve diagram showing that no light conversion structure is provided, Figure 7 A light transmittance curve diagram showing the light conversion structure is set. Figure 6 The middle curve 400 represents the light transmittance of the sample placed horizontally, and the curve 500 represents the light transmittance of the sample placed vertically. Obviously, Figure 6 In the figure, the curves are obviously different when the samples are placed in different directions. Figure 7 The light transmittance curves of samples placed horizontally and vertically are also shown in Figure 1, but the two are almost indistinguishable. It can be seen that after adopting the light conversion structure, the sample placement direction is not restricted, and the accuracy of the transmittance test is improved.

[0042] The specific structural form of the light conversion structure can be various, such as a quarter wave plate, but the quarter wave plate can only convert linear polarized light of a single band with a wavelength of 550nm into circular polarized light. In order to convert linear polarized light of more bands into circular polarized light and improve the transmittance, in some implementations of this embodiment, reference Figure 3 Along the emitting direction of the light source, the light conversion structure includes a first transparent substrate 1, a polarizing film layer 2, a complex refractive film layer 3 and a second transparent substrate 4 stacked in sequence, the polarizing film layer 2 is used to convert the light emitted by the light source into linear polarized light, and the complex refractive film layer 3 is used to convert the linear polarized light into circularly polarized light.

[0043] The material of the complex refractive film layer 3 refers to a material with different refractive indices in all directions, which can be formed by directional stretching of polymer materials. The complex refractive film layer has a large phase difference. When linear polarized light passes through the complex refractive film layer 3 with a large phase difference, the linear polarized light will be converted into circular polarized light. In addition, whether the external visible light can pass through the complex refractive film layer 3 in the full band is related to the phase difference (Re) of the complex refractive film layer 3, such as Figure 8 As shown, Figure 8is the transmittance of the full-band visible light (wavelength λ) corresponding to the complex refractive film layer with different phase difference values ​​(Re), and the formula is: I / I0=1 / 2·sin2(π·Re / λ), I0 is the intensity of the light before passing through the complex refractive film layer 3, and I is the intensity of the light after passing through the complex refractive film layer 3; wherein, curve 600 represents the transmittance when the phase difference value Re=800, and curve 700 represents the transmittance when the phase difference value Re=5000. It can be seen that the larger the phase difference value (Re), the more light that passes through the visible light band (that is, the greater the light intensity), and therefore a complex refractive film layer with a larger phase difference value is preferred.

[0044] Exemplarily, the phase difference value of the complex refractive film layer 3 is 5000nm-10000nm, and at this time, light of more wavelength bands can pass through the sample with the polarizer.

[0045] The complex refractive film is a type of phase difference film. After the transparent polymer film undergoes the alignment process (stretching), its molecular arrangement direction is concentrated in the alignment direction, causing the refractive index of light in all directions in the film to change. Such a film is called a phase difference film. Fig. 9 As shown, it is usually defined as follows: the direction of the maximum refractive index in the film plane is the direction of the slow phase axis (the direction of the arrow indicated by 800 in the figure), and the refractive index in this direction is nx; the direction orthogonal to the slow phase axis in the film plane is the forward axis direction, and the refractive index in this direction is ny; the refractive index in the vertical direction of the film is nz. The phase difference value Re of the film is (nx-ny)·d. It can be seen that the phase difference value Re of the complex refractive film layer is related to the thickness d of the complex refractive film layer. The larger the thickness d, the larger the phase difference value Re.

[0046] In specific implementation, although the larger the thickness of the complex refraction film layer 3, the larger the phase difference, the more light in the visible light band is transmitted, that is, the greater the intensity of the conversion of linear polarized light into circular polarized light. However, since current display devices tend to be thinner and lighter, a large thickness of the complex refraction film layer 3 is not conducive to the thinner and lighter display device. Therefore, in order to allow as much light as possible to pass through the visible light band while meeting the requirements of the thinner and lighter display device, in the above-mentioned display device provided in the embodiment of the present invention, the phase difference of the complex refraction film layer 3 is a preset value, wherein the preset value is 5000nm-10000nm. When the phase difference of the complex refraction film layer is 5000nm-10000nm, more light in the visible light band is transmitted, and the display device can also be thinner and lighter.

[0047] In some embodiments, the material of the complex refractive film layer is polyethylene terephthalate (PET) film or super retarder film (SRF) film. However, the phase difference of SRF is greater than that of PET, so in order to meet the requirements of lightness and thinness, SRF is preferably used.

[0048] In a specific embodiment, the complex refractive film layer adopts SRF, has a phase difference of 8000nm and a thickness of 75μm.

[0049] Exemplarily, in order to increase the transmittance of circularly polarized light passing through a sample with a polarizer, the angle between the stretching direction of the complex refracting film layer and the transmission axis of the polarizing film layer is ±45°±15°.

[0050] In a specific embodiment, the angle between the stretching direction of the complex refractive film layer 3 and the transmission axis of the polarizing film layer is ±45°, so that almost all circularly polarized light can pass through the sample with the polarizer, thereby improving the accuracy of the transmittance test.

[0051] Exemplarily, the first transparent substrate 1 and the polarizing film layer 2 are connected by pressure-sensitive adhesive, the polarizing film layer 2 and the complex refracting film layer 3 are connected by pressure-sensitive adhesive, and the complex refracting film layer 3 and the second transparent substrate 4 are connected by pressure-sensitive adhesive, but this is not limited to this. For example, optical adhesive can also be used.

[0052] In this embodiment, both the first transparent substrate 1 and the second transparent substrate 4 are glass substrates to ensure transparency, but the present invention is not limited thereto.

[0053] In this embodiment, the first transparent substrate 1 plays a supporting role, the second transparent substrate 4 plays a protective role, and the first transparent substrate 1 and the second transparent substrate 4 ensure the flatness of the complex refractive film layer 3 .

[0054] refer to Figure 10-13 In this embodiment, the transmittance testing device includes a mounting portion 2 for mounting a light source, a light intensity adjusting portion 3 for adjusting the light intensity, a stage 1 arranged directly above the light source, a stage adjusting portion for adjusting the height of the stage 1, a light intensity collection sensor 5, an eyepiece 6, a light intensity collection probe 7, etc. The structure of the transmittance testing device can refer to conventional transmittance testing equipment, and will not be repeated again.

[0055] In some implementations of this embodiment, in order to solve the problem of the polarization characteristics of light emitted by the light source affecting the accuracy of the transmittance test, a light conversion structure is set between the light source and the carrying surface of the stage, so that the light of the light source is converted into circularly polarized light, eliminating the influence of the polarization characteristics of the light and improving the accuracy of the transmittance test. There can be many specific setting positions of the light conversion structure. The setting method in this embodiment is introduced as follows.

[0056] refer to Fig.10 and Fig.11 In some implementations of this embodiment, the light conversion structure is integrated on the carrier 1, and a first groove 11 is provided in a first area of ​​the carrier 1. The first groove 11 extends in a direction from the carrier surface toward the light source, and a first light hole 12 is provided at the bottom of the first groove 11. The light conversion structure is accommodated in the first groove 11.

[0057] Exemplarily, the cross-sectional shape of the first groove 11 in the light emitting direction of the light source is an inverted trapezoid.

[0058] The shape of the first groove 11 is not limited to that described above. In this embodiment, an inverted trapezoidal structure is adopted to facilitate the placement of the light conversion structure.

[0059] refer to Fig.12 The first groove 11 is a stepped groove, and the first groove 11 includes a first sub-groove 101 and a second sub-groove 102. The second sub-groove 102 is extended from the bottom of the first sub-groove 101 toward the direction close to the light source. The setting of the second sub-groove 102 reduces the contact area with the light conversion structure, protects the first transparent substrate 1, and prevents the light conversion structure from directly contacting the first light hole 11, thereby avoiding damage to the lens (the collimating lens arranged at the first light hole).

[0060] refer to Fig.10 and Fig.13 In some implementations of this embodiment, the light conversion structure 10 is integrated and arranged on the light emitting side of the light source, and the transmittance testing device includes a mounting portion 2 for mounting the light source, and a second light through hole 21 is arranged on the mounting portion 2, and a receiving portion 8 for receiving the light conversion structure 10 is arranged on the light emitting side of the second light through hole 21:

[0061] The accommodating portion 8 is provided with a second groove 81, the light conversion structure 10 is accommodated in the second groove 81, the accommodating portion 8 includes a first surface facing the stage 1, and the second groove 81 is extended from the first surface to the direction close to the second light hole 21;

[0062] The accommodating portion 8 further includes a third groove 82 , which extends from the bottom of the second groove 81 toward the light source and penetrates the accommodating portion 8 , and a cross-sectional area of ​​an end of the third groove 82 away from the second groove 81 is greater than or equal to an area of ​​the second light hole 21 .

[0063] Exemplarily, in the light emitting direction of the light source, the cross-sectional shape of the second groove 81 is an inverted trapezoid.

[0064] Exemplarily, the mounting portion 2 and the accommodating portion 8 are integrated into an integral structure.

[0065] The mounting portion 2 and the accommodating portion 8 are integrated into an integral structure, and the original structure of the mounting portion 2 needs to be changed. In some embodiments, the accommodating portion 8 is directly arranged on the basis of the original structure of the transmittance test device, that is, the accommodating portion 8 and the mounting portion 2 are arranged separately, and there is no need to change the original structure. The accommodating portion 8 is directly connected to the mounting portion 2 and fixedly connected. The accommodating portion 8 and the mounting portion 2 can also be connected in a detachable manner. The area of ​​the opening end of the third groove 82 connected to the second groove 81 is smaller than the area of ​​the bottom of the second groove 81, that is, the second groove 81 and the third groove 82 form a stepped groove. The light conversion structure 10 is accommodated in the second groove 81. The setting of the third groove 82 allows the light emitted from the second light hole 21 to pass through, and plays a role in protecting the lens (a collimating lens for collimating light) arranged at the second light hole 21, and plays a role in protecting the light conversion structure 10.

[0066] It is to be understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present invention, but the present invention is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A transmittance testing device, comprising a light source and a stage located at the light emitting side of the light source, wherein the stage is provided with a carrying surface for carrying a sample, characterized in that: A light conversion structure is provided between the light source and the bearing surface, for converting the light emitted by the light source into circularly polarized light; Along the emission direction of the light source, the light conversion structure comprises a first transparent substrate, a polarizing film layer, a complex refractive film layer and a second transparent substrate stacked in sequence, the polarizing film layer is used to convert the light emitted by the light source into linear polarized light, and the complex refractive film layer is used to convert the linear polarized light into circular polarized light; The angle between the stretching direction of the complex refractive film layer and the transmission axis of the polarizing film layer is ±45°±15°; The phase difference value of the complex refraction film layer is 5000nm-10000nm; It comprises a mounting portion for mounting the light source, the mounting portion is provided with a second light through hole, and a receiving portion for receiving the light conversion structure is provided on the light exit side of the second light through hole: The accommodating portion is provided with a second groove, the light conversion structure is accommodated in the second groove, the accommodating portion includes a first surface facing the stage, and the second groove is extended in a direction from the first surface to the second light hole; The accommodating portion further includes a third groove, which extends from the bottom of the second groove toward the light source and passes through the accommodating portion, and a cross-sectional area of ​​an end of the third groove away from the second groove is greater than or equal to an area of ​​the second light-transmitting hole.

2. The transmittance testing device according to claim 1, characterized in that: The material of the complex-refracting film layer is polyethylene terephthalate or super complex-refracting polyester film.

3. The transmittance testing device according to claim 1, characterized in that: The first transparent substrate and the polarizing film layer are connected by a pressure-sensitive adhesive, the polarizing film layer and the complex refracting film layer are connected by a pressure-sensitive adhesive, and the complex refracting film layer and the second transparent substrate are connected by a pressure-sensitive adhesive.

4. The transmittance testing device according to claim 1, characterized in that: A first groove is formed in the first area of ​​the stage, and the first groove extends in a direction from the carrying surface toward the light source. A first light hole is formed at the bottom of the first groove, and the light conversion structure is accommodated in the first groove.

5. The transmittance testing device according to claim 4, characterized in that: The cross-sectional shape of the first groove in the light emitting direction of the light source is an inverted trapezoid.

6. The transmittance testing device according to claim 1, characterized in that: In the light emitting direction of the light source, the cross-sectional shape of the second groove is an inverted trapezoid.

7. The transmittance testing device according to claim 1, characterized in that: The mounting portion and the accommodating portion are integrated into an integral structure.

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