Polarizing composite sheet attaching control apparatus and method

Abstract

The present application relates to the technical field of imaging display, and especially relates to a polarized composite sheet attaching control device and method, which comprises a supporting subsystem, an attaching subsystem, a measuring subsystem and a control module; the supporting subsystem comprises a light source, a film carrier and a two-degree-of-freedom adjusting mechanism; the film carrier is used for flattening and fixing a first film sheet; the two-degree-of-freedom adjusting mechanism is used for adjusting the position of the film carrier and driving the film carrier to rotate; the attaching subsystem comprises a film sheet constraint module and an attaching roller; the film sheet constraint module is used for flattening and fixing a second film sheet; the measuring subsystem comprises a spectrometer, a polarized light detection sheet and a rotating mechanism; the spectrometer is used for receiving light emitted by the light source, the polarized light detection sheet is used for polarized filtering of light incident on the spectrometer; the rotating mechanism is used for driving the polarized light detection sheet to rotate; and the control module is used for detecting a relative angle. The present application can accurately regulate the relative angle between the light transmission directions of different layers of film sheets in the process of attaching and preparing a polarized composite sheet.

Description

Technical Field

[0001] This invention relates to the field of imaging display technology, and in particular to a polarizing composite sheet attachment control device and method. Background Technology

[0002] Polarizing composites are often used in imaging display optical paths, such as the typical Pancake optical path (ultra-short focal length optical folding optical path) of virtual reality near-eye display system and the birdbath optical path of augmented reality near-eye display system. If the light emitted from the display's light-emitting surface is non-circularly polarized, two types of polarizing composites are required, as shown in Figure 1(a) and Figure 1(b), respectively. If the light emitted from the display's light-emitting surface is circularly polarized, only the polarizing composite shown in Figure 1(a) is required.

[0003] As shown in Figure 1(a), the polarizing composite sheet comprises, from left to right, a linear polarizer (POL), a polarizing beam splitter (PBS), a quarter-wave plate (QWP), and an anti-reflector (AR). Similarly, as shown in Figure 1(b), the polarizing composite sheet also comprises, from left to right, an anti-reflector (AR), a quarter-wave plate (QWP), and a linear polarizer (POL). The anti-reflector (AR) is used to reduce surface reflection without affecting the polarization state of the transmitted light. These polarizing composite sheets often cannot be simply bonded together; specific requirements exist regarding the relative angles between the transmission directions of the POL, PBS, and QWP films. For the polarizing composite shown in Figure 1(a), the transmission direction of POL should coincide with the transmission direction of PBS as much as possible, and the angle between the transmission direction of PBS and the transmission direction of QWP should be as close as possible to 45°. For the polarizing composite shown in Figure 1(b), the angle between the transmission direction of QWP and the transmission direction of POL should be as close as possible to 45°.

[0004] To obtain a satisfactory polarizing composite sheet, the relative angles between the light-transmitting directions of different film layers need to be controlled during the bonding and fabrication process. Currently, existing technologies typically only consider the accuracy of film alignment and flatness during bonding, often relying solely on visual measurement to determine the relative angles between the light-transmitting directions of the two layers. For example, marking the light-transmitting directions of the films and then observing the relative angles is prone to error and makes it difficult to ensure that the relative angles between the light-transmitting directions accurately meet the preset requirements, resulting in a low yield. Currently, there is no bonding control equipment specifically designed for the production needs of polarizing composite sheets. Summary of the Invention

[0005] The purpose of this invention is to address at least some of the shortcomings mentioned above by providing an attachment control device and method that can precisely control the relative angles between the light transmission directions of different film layers during the attachment and preparation of polarization composite sheets, thereby improving the yield of polarization composite sheets.

[0006] To achieve the above objectives, the technical solution of the present invention is implemented as follows:

[0007] A polarizing composite sheet attachment control device is disclosed for attaching a polarizing composite sheet composed of a first film and a second film. The first film includes a linear polarizer (POL), or a combination of a linear polarizer (POL) and a polarizing beam splitter (PBS). The second film includes a quarter-wave plate (QWP). The polarizing composite sheet attachment control device includes: a support subsystem, an attachment subsystem, a measurement subsystem, and a control module.

[0008] The support subsystem includes a light source, a film stage, and a two-degree-of-freedom adjustment mechanism; the film stage is used to flatten and fix the first film to be attached; the light source and the first film are respectively located on both sides of the film stage; the two-degree-of-freedom adjustment mechanism is used to adjust the position of the film stage and drive the film stage to rotate.

[0009] The attachment subsystem is located on the side of the film stage that fixes the first film, and includes a film constraint module and an attachment roller; the film constraint module is used to flatten and fix the second film to be attached; the attachment roller is located on one side of the second film and is used to attach the first film and the second film after the measurement subsystem detects that the relative angle between the light transmission directions of the first film and the second film meets the preset target angle requirement;

[0010] The measurement subsystem includes a spectrometer, a polarizing detector, and a rotation mechanism. The measurement subsystem is located on the side of the attachment subsystem away from the support subsystem. The spectrometer is used to receive light emitted from the light source, and the polarizing detector is used to perform polarization filtering on the light incident on the spectrometer. The rotation mechanism is used to drive the polarizing detector to rotate, thereby changing the rotation angle of the polarizing detector relative to the polarizing composite plate.

[0011] The control module is used to determine whether the relative angle between the light intensity (including initial light intensity and transmitted light intensity) of the first film and the relative angle between the light transmission directions of the polarized light detection plate and the polarized composite plate, based on the relationship between the light intensity (including initial light intensity and transmitted light intensity) collected by the measurement subsystem, the phase retardation of the first film, the relative angle between the light transmission directions of the polarized light detection plate and the polarized composite plate, and the relative angle between the light transmission directions of the first film and the second film, conforms to a preset target angle.

[0012] Optionally, the control module is further configured to calculate the transmittance of the polarizing composite sheet based on the initial light intensity and the transmitted light intensity through the polarizing composite sheet, thereby verifying whether the film quality of the first film and the second film both meet the preset film quality requirements.

[0013] Optionally, the control module is further configured to calculate the phase delay of the quarter-wave plate based on the initial light intensity and the transmitted light intensity through the polarization composite plate, thereby verifying whether the quality of the second diaphragm meets the preset diaphragm quality requirements.

[0014] Optionally, the two-degree-of-freedom adjustment mechanism includes a linear slide that can move linearly and a turntable that can rotate.

[0015] Optionally, the support subsystem further includes a base, the two-degree-of-freedom adjustment mechanism is disposed at the top of the base, and the film stage is disposed at the top of the two-degree-of-freedom adjustment mechanism.

[0016] Optionally, the two-degree-of-freedom adjustment mechanism is mounted on the base via a slide rail.

[0017] Optionally, the support subsystem further includes a negative pressure generator;

[0018] The membrane stage has air holes; the negative pressure generator is connected to the air holes of the membrane stage through an air pipe to create a negative pressure between the first membrane and the membrane stage.

[0019] Optionally, the diaphragm constraint module includes two sets of oppositely arranged clamps, each set of clamps including a pair of parallel and adjustable-spaced round bars, and the two sets of clamps are used to clamp the two sides of the second diaphragm respectively.

[0020] Optionally, the rotating mechanism includes a rotating stage, the polarizing light detector is disposed above the rotating stage, and the rotating stage has a through hole at its center for light transmission.

[0021] A method for controlling the attachment of a polarizing composite sheet, implemented using the polarizing composite sheet attachment control device as described in any of the above claims, includes the following steps:

[0022] The initial light intensity of the light emitted by the light source was measured by a spectrometer when the first and second membranes were not placed.

[0023] The first film to be attached is flattened and fixed using a film carrier stage;

[0024] The second diaphragm to be attached is flattened and fixed by the diaphragm constraint module;

[0025] The distance between the first diaphragm and the second diaphragm is adjusted using a two-degree-of-freedom adjustment mechanism;

[0026] The relative angle between the light transmission directions of the first and second films is coarsely adjusted using a two-degree-of-freedom adjustment mechanism.

[0027] The rotating polarizing light detector obtains the initial light intensity, transmitted light intensity, phase retardation of the first film, rotation angle of the polarizing light detector, and the relationship between the relative angles between the transmission directions of the first and second films through the measurement subsystem and control module; calculates the target rotation angle of the polarizing light detector based on the preset target angle between the transmission directions of the first and second films, and adjusts the polarizing light detector to the target rotation angle;

[0028] The rotating stage is used to fine-tune the relative angle between the light transmission directions of the first and second films. At the same time, the transmitted light intensity is collected by the measurement subsystem to detect whether the actual relative angle between the light transmission directions of the first and second films meets the preset target angle; until the relative angle between the light transmission directions of the first and second films meets the preset target angle requirement.

[0029] A polarizing composite sheet is obtained by attaching the second film and the first film using an attachment roller.

[0030] Optionally, before fine-tuning the relative angle between the light transmission directions of the first film and the second film, the following steps are also included:

[0031] Based on the initial light intensity and the transmitted light intensity through the polarizing composite sheet, the transmittance of the polarizing composite sheet is calculated to determine whether the quality of the first and second films both meet the preset film quality requirements. If so, the process continues.

[0032] Optionally, before fine-tuning the relative angle between the light transmission directions of the first film and the second film, the following steps are also included:

[0033] Based on the initial light intensity and the transmitted light intensity through the polarization composite sheet, the phase delay of the quarter-wave plate is calculated to verify whether the quality of the second diaphragm meets the preset diaphragm quality requirements.

[0034] The above-mentioned technical solution of the present invention has the following advantages: The present invention provides a polarizing composite sheet bonding control device and method; the device includes a support subsystem, a bonding subsystem, a measurement subsystem, and a control module; wherein, the support subsystem is used to flatten and fix the first film to be bonded, and can adjust the position and light transmission direction of the first film; the bonding subsystem is used to flatten and fix the second film to be bonded; the measurement subsystem and the control module are used to detect whether the relative angle between the light transmission directions of the first film and the second film meets the preset target angle; the support subsystem makes fine adjustments based on the detection results; and finally, the bonding subsystem bonds the first film and the second film to obtain a polarizing composite sheet. The present invention can accurately control the relative angle between the light transmission directions of different layers of films during the bonding and preparation of polarizing composite sheets, thereby producing high-quality polarizing composite sheets and improving the yield of polarizing composite sheets. Attached Figure Description

[0035] Figure 1(a) is a schematic diagram of the diaphragm assembly included in a polarization composite sheet;

[0036] Figure 1(b) is a schematic diagram of another type of polarization composite sheet containing a combination of films;

[0037] Figure 2 This is a schematic diagram of a polarization composite sheet attachment control device provided in an embodiment of the present invention;

[0038] Figure 3 This is a schematic diagram of a support subsystem structure provided in an embodiment of the present invention;

[0039] Figure 4 This is a schematic diagram of another support subsystem structure provided in an embodiment of the present invention;

[0040] Figure 5 This is a schematic diagram of a film carrier stage structure provided in an embodiment of the present invention;

[0041] Figure 6 This is a schematic diagram of an attachment subsystem structure provided in an embodiment of the present invention;

[0042] Figure 7 This is a schematic diagram of the usage state of a diaphragm constraint module structure provided in an embodiment of the present invention;

[0043] Figure 8 This is a schematic diagram of the steps of a polarizing composite sheet attachment control method provided in an embodiment of the present invention;

[0044] Figure 9 This is a schematic diagram illustrating the conventions for the angle symbols between the various diaphragms involved in the detection principle.

[0045] In the diagram: 11: Base; 12: Linear slide; 13: Turntable; 14: Light source; 15: Film stage; 151: Negative pressure generator; 152: Air hole; 153: Air nozzle; 154: Air tube; 16: First diaphragm; 17: Slide rail;

[0046] 21: Second diaphragm; 22: Diaphragm constraint module; 221: Round bar; 23: Attachment roller; 31: Spectrometer; 32: Polarizing light detector; 33: Rotation mechanism. Detailed Implementation

[0047] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0048] This invention provides an attachment control device and method for the production of polarizing composite films. While ensuring the quality of the attached film, it can precisely control the relative angle between the light transmission directions of different layers of film, thereby improving the yield.

[0049] like Figure 2 As shown in the embodiment of the present invention, a polarizing composite sheet attachment control device is provided for attaching a polarizing composite sheet composed of a first film and a second film. The first film includes a linear polarizer (POL), or the first film includes a combination of a linear polarizer (POL) and a polarizing beam splitter (PBS). The second film includes a quarter-wave plate (QWP).

[0050] The polarization composite sheet attachment control device includes: a support subsystem, an attachment subsystem, a measurement subsystem, and a control module; wherein...

[0051] The support subsystem includes a light source 14, a film stage 15, and a two-degree-of-freedom adjustment mechanism. The film stage 15 is used to flatten and fix the first film 16 to be attached. The light source 14 and the first film 16 are located on opposite sides of the film stage 15. The two-degree-of-freedom adjustment mechanism enables adjustment of two degrees of freedom, used to adjust the position of the film stage 15 and drive the film stage 15 to rotate. The film stage 15 is preferably made of a light-transmitting material and has at least one flat surface to flatten and fix the first film 16 to be attached. For example, the film stage 15 can be made of a flat transparent glass. The two-degree-of-freedom adjustment mechanism can change the distance between the first film 16 and the attachment subsystem, as well as the light transmission direction of the first film 16. If the film stage 15 is light-transmitting, the light source 14 can be embedded between the two-degree-of-freedom adjustment mechanism and the film stage 15, located at the center of the two-degree-of-freedom adjustment mechanism, or it can be placed in other locations, as long as the light can pass through the first film 16, the second film 21, and finally be received by the spectrometer 31.

[0052] The attachment subsystem is located on the side of the film stage 15 where the first film 16 is fixed. The attachment subsystem includes a film constraint module 22 and an attachment roller 23. The film constraint module 22 is used to flatten and fix the second film 21 to be attached. The attachment roller 23 is located on one side of the second film 21 and is used to attach the first film 16 and the second film 21 after the measurement subsystem detects that the relative angle between the light transmission directions of the first film 16 and the second film 21 meets the preset target angle requirement. Figure 2 As shown, the attachment roller 23 is located on the side of the second diaphragm 21 away from the first diaphragm 16, so that after the diaphragm combination consisting of the first diaphragm 16 and the second diaphragm 21 meets the preset requirements, pressure is applied to attach the second diaphragm 21 to the first diaphragm 16. The specific structure of the attachment roller 23 and the attachment method (such as the application of optical adhesive between the first diaphragm 16 and the second diaphragm 21) can be found in the prior art and will not be described further here.

[0053] The measurement subsystem is located on the side of the attachment subsystem away from the support subsystem. The measurement subsystem includes a spectrometer 31, a polarizing detector 32, and a rotation mechanism 33. The spectrometer 31 is used to receive the light emitted from the light source 14 and collect the light intensity information of each spectrum. The polarizing detector 32 is used to perform polarization filtering on the light incident on the spectrometer 31. The rotation mechanism 33 is used to drive the polarizing detector 32 to rotate, thereby changing the light transmission direction of the polarizing detector 32, that is, changing the direction of polarization filtering. The measurement subsystem is used to detect the relative angle between the light transmission directions of the first diaphragm 16 and the second diaphragm 21.

[0054] By selecting the emission spectrum of the light source 14, measurements can be performed within different wavelength ranges. For example, if the light source 14 emits a visible spectrum, the measured result is the property of the polarization composite sheet in the visible spectrum; if the light source 14 emits an infrared spectrum, the result is the infrared spectral property. Of course, regardless of the selection, the spectral band of the light emitted by the light source 14 cannot exceed the measurement range of the spectrometer 31 and the response range of the polarization detection sheet 32.

[0055] The control module is used to measure the light intensity (including the initial light intensity I) collected by the measurement subsystem. in and transmitted light intensity I out The relationship between the phase retardation δ of the first diaphragm, the relative angle μ between the transmission directions of the polarizing detector and the polarizing composite sheet, and the relative angle β between the transmission directions of the first and second diaphragms is determined. After determining the phase retardation δ of the first diaphragm and the relative angle between the transmission directions of the polarizing detector and the polarizing composite sheet, it is checked whether the relative angle between the transmission directions of the first and second diaphragms conforms to a preset target angle. Since the polarizing detector and the polarizing composite sheet are in a relative rotational relationship, the relative angle μ between the transmission directions of the polarizing detector and the polarizing composite sheet can be calculated using the rotation angle θ of the polarizing detector. Therefore, in the calculation of the relative angle β between the transmission directions of the first and second diaphragms, the rotation angle θ of the polarizing detector can be used instead of the relative angle μ between the transmission directions of the polarizing detector and the polarizing composite sheet as a variable for numerical calculation.

[0056] Preferably, considering that the quality of films from different manufacturers, and even different production batches from the same manufacturer, varies in actual production, the measurement subsystem can also measure the transmittance of the polarization composite sheet by collecting the original light intensity and the light intensity after passing through the polarization composite sheet (i.e., transmitted light intensity). This allows for the detection of the film quality of the first film 16 and the second film 21, ensuring that both the first film 16 and the second film 21 are of good quality and meet the preset film quality requirements. This measurement step can be performed when the two films are close to each other but not yet bonded together.

[0057] Furthermore, preferably, the measurement subsystem can also measure the phase retardation of the second diaphragm 21 (i.e., QWP) by collecting the original light intensity and the light intensity after passing through the polarizing composite sheet (i.e., transmitted light intensity), thereby detecting the diaphragm quality of the second diaphragm 21 and determining that the second diaphragm 21 itself is a good product and meets the preset diaphragm quality requirements. This measurement step can be performed when the two diaphragms are close to each other but not bonded together.

[0058] like Figure 2As shown, the present invention provides a polarizing composite sheet attachment control device. A light source 14 and a spectrometer 31 are respectively disposed on opposite sides of a film stage 15. Light emitted from the light source 14 passes through the film stage 15, then sequentially through a first film 16, a second film 21, and a polarizing light detector 32, before entering the spectrometer 31. Through a two-degree-of-freedom adjustment mechanism, the linear distance between the first film 16 and the second film 21 can be flexibly adjusted. The first film 16 can also be rotated as needed to change its light transmission direction, while the second film 21 remains stationary, thus changing the relative angle between their light transmission directions. Using the measurement results from the measurement subsystem, the film quality of the first film 16 and the second film 21 can be determined, as well as the relative angle between their light transmission directions. Based on the transmitted light intensity measured by the measurement subsystem, the relative angle between the transmission directions of the first diaphragm 16 and the second diaphragm 21 is obtained. A two-degree-of-freedom adjustment mechanism is used to finely adjust the transmission direction of the first diaphragm 16 until the combination of the first diaphragm 16 and the second diaphragm 21 meets the preset requirements. Finally, the first diaphragm 16 and the second diaphragm 21 are bonded together by the bonding roller 23 to obtain the polarization composite sheet. Because the measurement subsystem is used for actual measurement, the combination relationship between the first diaphragm 16 and the second diaphragm 21 can be repeatedly adjusted before final bonding, allowing for fine adjustment of the relative angle between their transmission directions. The polarization composite sheet bonding control equipment provided by this invention can produce high-quality polarization composite sheets that meet the requirements, effectively improving the yield rate of polarization composite sheet preparation.

[0059] To effectively utilize gravity, such as Figure 2 As shown, the preferred support subsystem is located at the bottom of the attachment subsystem, and the attachment subsystem is located at the bottom of the measurement subsystem. When the first diaphragm 16 is flattened and fixed on the film carrier stage 15, the gravity of the first diaphragm 16 can assist in its fixation. The first diaphragm 16 and the second diaphragm 21 are bonded together by the attachment roller 23, and the gravity of the attachment roller 23 can also facilitate the bonding of the first diaphragm 16 and the second diaphragm 21.

[0060] Optionally, such as Figure 2 As shown, the rotating mechanism 33 includes a rotating stage, and a polarizing light detector 32 is disposed on the rotating stage (either above or below). A through hole for light transmission is opened in the center of the rotating stage so that light passes through the polarizing light detector 32 and is incident on the spectrometer 31.

[0061] Optionally, the control module is further configured to generate control commands based on the relative angle between the light transmission directions of the first diaphragm 16 and the second diaphragm 21 and a preset target angle requirement, and send these commands to a two-degree-of-freedom adjustment mechanism. The two-degree-of-freedom adjustment mechanism adjusts the light transmission direction of the first diaphragm 16, thereby changing the relative angle between the light transmission directions of the first diaphragm 16 and the second diaphragm 21. In this embodiment, the control module can automatically and precisely adjust the first diaphragm 16 until the relative angle between the light transmission directions of the first diaphragm 16 and the second diaphragm 21 meets the preset target angle requirement. Preferably, the control module is further configured to calculate the transmittance of the polarization composite sheet based on the initial light intensity and the transmitted light intensity through the polarization composite sheet, thereby verifying whether the quality of the first and second diaphragms both meet the preset film quality requirements. If the control module determines, based on the measurement data from the spectrometer 31, that the quality of the first diaphragm 16 and the second diaphragm 21 does not meet the preset film quality requirements, it can issue a prompt to remind the user to replace them. Similarly, the control module is also used to calculate the phase delay of the quarter-wave plate based on the initial light intensity and the transmitted light intensity through the polarization composite plate, so as to verify whether the quality of the second diaphragm meets the preset diaphragm quality requirements.

[0062] Optionally, such as Figure 3 and Figure 4 As shown, the two-degree-of-freedom adjustment mechanism includes a linear slide 12 capable of linear movement and a turntable 13 capable of rotational movement. The combination of the linear slide 12 and the turntable 13 enables two-degree-of-freedom adjustment of the film-carrying stage 15. The film-carrying stage 15 can be mounted on either the linear slide 12 or the turntable 13.

[0063] Furthermore, the support subsystem may also include a base 11, a two-degree-of-freedom adjustment mechanism disposed at the top of the base 11, and a film stage 15 disposed at the top of the two-degree-of-freedom adjustment mechanism. In this embodiment, the base 11 serves to stabilize the two-degree-of-freedom adjustment mechanism. Figure 3 As shown, in one embodiment, a linear slide 12 is mounted on a base 11 and can move linearly up and down. A turntable 13 is rotatably mounted on the linear slide 12, and a film carrier stage 15 is mounted on top of the turntable 13. Figure 4 As shown, in another embodiment, the turntable 13 is rotatably mounted on the base 11, the linear slide 12 is mounted on the turntable 13, and the film carrier stage 15 is mounted on the top of the linear slide 12.

[0064] Furthermore, the two-degree-of-freedom adjustment mechanism is mounted on the base 11 via a slide rail 17, and the two-degree-of-freedom adjustment mechanism can slide along the slide rail 17. Figure 4 As shown, the slide rail 17 can be used to pull the support subsystem out from under the attachment subsystem to avoid obstruction and facilitate the feeding of the first diaphragm 16 and the second diaphragm 21.

[0065] Optionally, the support subsystem also includes a negative pressure generator 151, such as Figure 5 As shown, the film carrier stage 15 has air holes 152; a negative pressure generator 151 is connected to the air holes 152 of the film carrier stage 15 via an air tube 154, used to create negative pressure between the first membrane 16 and the film carrier stage 15, thereby fixing the first membrane 16 to one side of the film carrier stage 15. The negative pressure generator 151 is also a vacuum generator. The air holes 152 can be uniformly distributed small holes that penetrate the film carrier stage 15, with an air nozzle 153 connected to one side for connection to the air tube 154. Through negative pressure, it can be ensured that the first membrane 16 is always flatly fixed on the film carrier stage 15 during the application process and cannot move freely. Of course, except... Figure 5 In addition to the scheme shown, the support subsystem may also use other matching constraint components or clamps to cooperate with the film stage 15 to flatten and fix the first diaphragm 16.

[0066] Optionally, such as Figure 6 and Figure 7 As shown, the diaphragm constraint module 22 includes two sets of opposing clamps. Each set of clamps includes a pair of parallel and adjustable-spaced round bars 221. The two sets of clamps are used to clamp the two sides of the second diaphragm 21 respectively, so that the second diaphragm 21 is flattened and fixed. Figure 2 and Figure 6 As shown, when the attaching roller 23 moves, the height of the second diaphragm 21 will inevitably change. This requires that the diaphragm constraint module 22 cannot rigidly constrain the second diaphragm 21, otherwise it is easy to cause the second diaphragm 21 to tear or shift. Figure 7 As shown, a diaphragm constraint module 22 includes two pairs of adjustable-spaced cylindrical bars 221 for clamping a second diaphragm 21. The clamping degree of the second diaphragm 21 is adjusted by adjusting the spacing between the cylindrical bars 221, and the tension of the second diaphragm 21 is adjusted by the distance between the two sets of clamps. This effectively counteracts the sagging tendency caused by the weight of the second diaphragm 21, achieving flattening and fixation. It also provides the second diaphragm 21 with a certain degree of freedom when the attachment roller 23 moves, preventing the second diaphragm 21 from tearing or shifting. To adjust the position of each cylindrical bar 221, the polarizing composite sheet attachment control device should also include a corresponding clamp adjustment mechanism. The specific clamp adjustment mechanism can refer to the prior art and will not be further described here. The diameter, length, and specific position of the cylindrical bars 221 can be set according to actual needs and will not be further limited here. Furthermore, if necessary, the tilt angle of the second diaphragm 21 can also be adjusted by adjusting the height difference between the two clamps.

[0067] As described above, the first membrane 16 includes POL, or the first membrane 16 includes a combination of POL and PBS, and the second membrane 21 includes QWP. The first membrane 16 being POL and the second membrane 21 being QWP can be used to fabricate the polarizing composite sheet shown in FIG. 1(b); the first membrane 16 being PBS and POL, and the second membrane 21 being QWP, with PBS disposed between POL and QWP, can be used to fabricate the polarizing composite sheet shown in FIG. 1(a). The characteristic angle of the light transmission direction between the first membrane 16 and the second membrane 21 corresponds to the relative angle between the light transmission direction of QWP and the adjacent membrane layer (POL or PBS). Furthermore, the first membrane 16 and the second membrane 21 can also be composite membranes including an AR film. Since the antireflective film AR is a non-polarizing film, it has no effect on the relationship between the transmitted light intensity and the relative angle of the light transmission direction between the two membranes. The above-described polarizing composite sheet attachment control device is also applicable to the attachment control of polarizing composite sheets including antireflective films.

[0068] like Figure 8 As shown, the present invention also provides a polarizing composite sheet attachment control method, implemented using the polarizing composite sheet attachment control device as described in any of the above embodiments, comprising the following steps:

[0069] Step 800: Measure the initial light intensity of the light emitted by the light source 14 when no material is loaded using the spectrometer 31; the unloaded condition is that the first film 16 and the second film 21 to be attached are not set; preferably, after the equipment is powered on, a period of time should be waited for the light intensity of the light source 14 to stabilize.

[0070] Step 802: Flatten and fix the first membrane 16 to be attached using the membrane stage 15; the first membrane 16 includes POL, or the first membrane 16 includes a combination of PBS and POL.

[0071] Step 804: The second membrane 21 to be attached is flattened and fixed by the membrane constraint module 22; the second membrane 21 includes a QWP.

[0072] Step 806: Adjust the distance between the first diaphragm 16 and the second diaphragm 21 using a two-degree-of-freedom adjustment mechanism; as follows: Figure 3 and Figure 4 As shown, the height of the first film 16 can be changed by adjusting the film stage 15 through the linear slide 12; the distance between the first film 16 and the second film 21 should be appropriate. If it is too small, it may affect the rotation of the first film 16. If it is too large, it may cause the second film 21 to tear or the relative angle between the light transmission directions of the first film 16 and the second film 21 to change during the application process.

[0073] Step 808: Using a two-degree-of-freedom adjustment mechanism, coarsely adjust the relative angle between the light transmission directions of the first diaphragm 16 and the second diaphragm 21; as shown... Figure 3 and Figure 4 As shown, the direction of light transmission of the first film 16 can be changed by rotating the film stage 15 through the turntable 13.

[0074] Step 810: Rotate the polarizing light detector. Through the measurement subsystem, the control module obtains the initial light intensity I of the light passing through the polarizing composite plate. in Light intensity I out The relationship between the phase retardation δ of the first diaphragm, the rotation angle θ of the polarization detection plate, and the relative angle β between the transmission directions of the first and second diaphragms: I out =I in f(δ, θ, β); then, based on the preset target angle β0 (β0 = 45°) between the light transmission directions of the first and second films, the target rotation angle of the polarized light detection sheet is calculated, and the polarized light detection sheet is adjusted to the target rotation angle;

[0075] In the measurement results, the transmitted light intensity I out and initial light intensity I in The ratio is related to the phase retardation δ of the quarter-wave plate, the rotation angle θ of the polarization detection plate, and the relative angle β between the transmission directions of the first and second films. The phase retardation δ of the quarter-wave plate varies for different wavelengths of light. Multispectral data is obtained using a spectrometer to measure the polarization modulation effect of the polarization composite plate on natural or multicolor light, which is of great significance for near-eye color displays.

[0076] Step 812: Rotate the film stage to fine-tune the relative angle between the light transmission directions of the first and second films. Simultaneously, the transmitted light intensity I is collected by the measurement subsystem. out The actual relative angle between the light transmission directions of the first diaphragm and the second diaphragm is detected to meet the preset target angle β0; until the relative angle between the light transmission directions of the first diaphragm 16 and the second diaphragm 21 meets the preset target angle requirement;

[0077] Step 814: The second film 21 and the first film 16 are attached by the attachment roller 23 to obtain a polarizing composite film.

[0078] Preferably, before fine-tuning the relative angle between the light transmission directions of the first diaphragm 16 and the second diaphragm 21 in step 810, the following step is further included: based on the initial light intensity I collected by the measurement subsystem... in The transmitted light intensity I through the polarizing composite sheet outThe transmittance τ of the polarizing composite sheet is calculated to determine whether the transmittance of the first film 16 and the second film 21 meets the preset film quality requirements. If yes, the process continues; otherwise, the application should be stopped and the current first film 16 and the second film 21 should be replaced to ensure that the first film 16 and the second film 21 applied in subsequent processes are all good products.

[0079] Preferably, before fine-tuning the relative angle between the light transmission directions of the first diaphragm 16 and the second diaphragm 21 in step 810, the following step is further included: based on the initial light intensity I collected by the measurement subsystem... in The transmitted light intensity I through the polarizing composite sheet out The phase delay of the quarter-wave plate is calculated to determine whether the quality of the second diaphragm 21 meets the preset diaphragm quality requirements. If yes, the process continues; otherwise, the attachment should be stopped and the current second diaphragm 21 should be replaced.

[0080] The following is combined Figure 9 The angle model of the polarization composite sheet measurement system shown illustrates the measurement process of the relevant parameters of the polarization composite sheet, especially the measurement and calculation processes involved in the specific implementation of steps 810 and 812.

[0081] Because the detection process of composite polarizers requires the use of polarizing light detectors, which are essentially linear polarizers, i.e., POL. Figure 9 In the angular model of the polarization composite sheet measurement system shown, in order to distinguish between the POL that serves as the polarization light detector and the POL in the polarization composite sheet, the polarization light detector is defined as the spectrometer front POL, and each film layer in the polarization composite sheet is defined as composite sheet QWP, composite sheet PBS, and composite sheet POL.

[0082] like Figure 9 As shown, taking a polarization composite sheet including composite sheet QWP, composite sheet PBS, and composite sheet POL as an example, and defining the symbols for the included angles and transmittance of each sheet, the Jones matrix is ​​obtained as follows:

[0083] [1] The world coordinate system is defined as OXY;

[0084] [2] The angle between the transmission axis and the OX axis of the composite sheet POL is α, its transmittance is τ0, and its extinction ratio is assumed to be in an ideal state of approximately infinity. Then the Jones matrix is ​​obtained as follows:

[0085] [3] The composite film PBS has two transmission axes, namely the transmission axes of s-ray and p-ray, which are orthogonal. Here, we define the polarization state of the transmitted light from the composite film POL as s, and the angle between the s-ray transmission axis of the composite film PBS and the composite film POL as γ. Then, the angle between it and the OX axis is α+γ, its transmittance is τ1, and its extinction ratio is in an ideal state of approximately infinity. Then, its Jones matrix is ​​obtained as follows:

[0086]

[0087] [4] The angle between the fast axis of the composite QWP and the composite PBS is β, its phase retardation is δ, and its transmittance is τ. q Therefore, its Jones propagation matrix is ​​obtained as follows:

[0088]

[0089] [5] The transmission axis of the pre-amplifier POL makes an angle θ with the OX axis and an angle μ with the composite PBS. The transmittance is τ2. Assuming the extinction ratio is approximately infinite, its Jones matrix is:

[0090]

[0091] [6] The intensity of the incident light source is I in Then the Jones vector of the incident light is:

[0092]

[0093] It should be noted that in the actual measurement of the polarization composite sheet, the value of α is arbitrary and only related to the conventional world coordinate system direction; the angle of β fluctuates around 45°, and the fluctuation range of β will not exceed ±1° through the attachment process of the polarization composite sheet, the angle of γ will not exceed 1°, and δ fluctuates around 90°, with δ showing different values ​​with wavelength; for the polarization composite sheet sample to be measured placed on the sample stage, β, γ and δ should be fixed values; during the measurement process, only θ will change with the relative rotation of the spectrometer pre-position POL and the polarization composite sheet, thus affecting the change of μ, where θ=α+γ+μ. (6)

[0094] The following example illustrates how measurement can be achieved by rotating the sample stage to change the relative angle between the polarizing detector and the polarizing composite plate.

[0095] Interpolate each Jones matrix sequentially with the incident Jones vector E. in Multiplying these yields the Jones vector E of the light received by the spectrometer. out Since the spectrometer can only obtain light intensity, a conjugate multiplication is performed to obtain the final light intensity I. out :

[0096] E out =J p2 J qwp J p1 J p0 E in (7)

[0097]

[0098] Observing the above formula, we can see that I out It is related to the aforementioned angles, phase retardation, transmittance, and incident light intensity.

[0099] When the tested membrane is in an ideal state, i.e., β = 45° (the angle between the transmission directions of the composite QWP and the composite PBS is 45°, and the transmission directions of the composite PBS and the composite POL coincide), δ = 90° (QWP brings a perfect quarter-phase delay), substituting into the above equation (8), we can see that I at this time out The magnitude is independent of μ, meaning that the light intensity received by the spectrometer remains constant regardless of how the front POL of the spectrometer is rotated.

[0100] The following describes the specific process of measuring the phase delay δ of the QWP composite sheet, the transmittance τ of the polarization composite sheet, and the angle β between the transmission directions of the first and second films in the polarization composite sheet.

[0101] 1. Measurement procedure of the angle γ between composite sheet POL and composite sheet PBS:

[0102] When the POL of the spectrometer is rotated, θ and μ change. Due to the special properties of the polarization state, it can be predicted that the light intensity corresponding to a certain θ and μ will be recorded as I. μ When μ changes to μ+π / 2, record the corresponding light intensity as I. μ+π / 2 Through mathematical derivation, we obtain:

[0103]

[0104] It can be seen that: the sum of orthogonal light intensities I sum It is independent of θ, μ, β, and δ. in It can be measured; if τ0τ1τ2τ is obtained... q And by assuming that the world coordinate system OX coincides with the light transmission direction of the composite sheet POL (i.e., α = 0), the value of γ is obtained.

[0105] For transmittance τ0τ1τ2τ q It can be obtained through measurement. Multiple I values ​​are recorded by placing the films in the composite polarizer layer by layer. sum The transmittance τ0, τ1, and τ2 can be calculated using equation (9). q And τ2, then calculate τ0τ1τ2τq Then γ can be obtained. The transmittance τ of the polarizing composite sheet is defined as τ0, τ1, τ... q The product of these two factors. The transmittance τ of the polarizing composite sheet can be calculated through the above measurement process, where τ = τ0τ1τ. q .

[0106] 2. Measurement process of the angle β between the transmission direction of composite POL and composite QWP, and the phase delay δ of composite QWP:

[0107] to I out Taking the derivative of μ and setting it to 0, we obtain that μ satisfies the following condition:

[0108]

[0109] When μ satisfies the above equation, I out The maximum or minimum value is obtained, and the difference between μ corresponding to the maximum and minimum values ​​is π / 2. Substituting μ and μ+π / 2 that satisfy the above equation into the above equation, we can obtain I. max and I min The expression.

[0110] During testing, the sample stage is rotated (equivalent to rotating the pre-position POL of the spectrometer), and the spectrometer readings are recorded simultaneously.

[0111]

[0112] When the light intensity reaches its maximum I max At this time, record the angle of the rotary table as μ. max Continue rotating the sample stage by 90° until the light intensity reaches its minimum value, which should be recorded as I. min Based on the processes described above, the following relationship exists:

[0113]

[0114]

[0115] The above derivation is for a single-wavelength numerical model. For multi-wavelength models, each wavelength also follows this model.

[0116] For a given measurement sample, the value of β is the angle between the composite sheet QWP and the composite sheet POL or composite sheet PBS, and the measured value of β does not change with wavelength; however, the phase retardation δ of the composite sheet QWP varies with different wavelengths. Based on this property, multispectral intensity measurements using a spectrometer can be performed to obtain the response of the polarization composite sheet to different wavelengths, thus revealing various properties of the polarization composite sheet at different wavelengths.

[0117] The process of calculating β and δ according to equations (11), (12) and (13) is as follows:

[0118] Align the world coordinate system OXY with the XY axis of the sample stage. At this point, the angle reading of the sample stage is the magnitude of θ. As mentioned earlier, it is agreed that the OX axis of the world coordinate system OXY coincides with the light transmission direction of the composite sheet POL (i.e., α = 0), and the specific value of γ has been obtained. According to the relationship θ = α + γ + μ, the magnitude of μ can be obtained.

[0119] Rotate the sample stage, record the angle readings and the spectrometer light intensity readings, and obtain multiple sets of μ and I. out The value is illustrated below: Data is recorded at 0.5° intervals, 720 sets of data are collected within a 360° range, and 720 I values ​​are obtained simultaneously. sum The size of these I; theoretically these I sum The values ​​should be equal, but in practice, errors will always be introduced. Therefore, it is preferable to choose I. sum The average value is used to reduce error.

[0120] As mentioned above, the β of a single polarization composite does not change with wavelength, while δ varies with wavelength. A spectrometer can be used to collect transmission intensity across a multispectral range. For example, the sampling wavelength range is 300–750 nm, with a sampling accuracy of 0.1 nm, meaning that 4500 data points can be obtained in a single sampling. According to equation (13) I... out / I sum The expressions and actual values ​​were used to establish 720*4500=3240000 equations using 720 sets of collected data. The system of equations was solved to calculate the values ​​of β and δ.

[0121] The above detection method, taking a polarizing composite sheet containing QWP, PBS, and POL simultaneously as an example, describes the detection process of the polarizing composite sheet. When the polarizing composite sheet contains only QWP and POL, setting γ = 0° and τ1 = 1, the above calculation formula can be simplified, and the angles of the transmission directions of the first and second films in the polarizing composite sheet, the phase retardation of the quarter-wave plate, and the transmittance of the polarizing composite sheet can still be obtained. These will not be elaborated further here.

[0122] In summary, this invention provides a polarizing composite sheet attachment control device and method. It utilizes a support subsystem and an attachment subsystem to fix the first and second films to be attached, respectively. A measurement subsystem and a control module determine the relative angle between the light transmission directions of the first and second films. By precisely controlling the relative angle between the light transmission directions of different film layers through the support subsystem, a high-quality polarizing composite sheet is obtained, improving the yield rate of polarizing composite sheet preparation. The attachment control device and method of this invention have a wide range of applications and can attach different types of polarizing composite sheets. Not only can it actively adjust the relative positions of the films during the attachment process based on the measurement results through an active alignment process, ensuring that the relative angle of the final composite sheet reaches the target value, but it can also detect the performance of the films to be attached before attachment to ensure the yield rate of the polarizing composite sheet.

[0123] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A polarizing composite sheet attaching control apparatus for attaching a polarizing composite sheet composed of a first film sheet including a linear polarizing sheet and a second film sheet including a quarter wave sheet, characterized by, include: The system comprises a support subsystem, an attachment subsystem, a measurement subsystem, and a control module; among which, The support subsystem includes a light source, a film stage, and a two-degree-of-freedom adjustment mechanism; the film stage is used to flatten and fix the first film to be attached; the light source and the first film are respectively located on both sides of the film stage; the two-degree-of-freedom adjustment mechanism is used to adjust the position of the film stage and drive the film stage to rotate. The attachment subsystem is located on the side of the film stage that fixes the first film, and includes a film constraint module and an attachment roller; the film constraint module is used to flatten and fix the second film to be attached; the attachment roller is located on one side of the second film and is used to attach the first film and the second film after the measurement subsystem detects that the relative angle between the light transmission directions of the first film and the second film meets the preset target angle requirement; The measurement subsystem includes a spectrometer, a polarizing detector, and a rotation mechanism. The measurement subsystem is located on the side of the attachment subsystem away from the support subsystem. The spectrometer is used to receive light emitted from the light source, and the polarizing detector is used to perform polarization filtering on the light incident on the spectrometer. The rotation mechanism is used to drive the polarizing detector to rotate, thereby changing the rotation angle of the polarizing detector relative to the polarizing composite plate. The control module is used to determine whether the relative angle between the light intensity collected by the measurement subsystem, the phase delay of the first film, the relative angle between the transmission directions of the polarized light detection plate and the polarized composite plate, and the relative angle between the transmission directions of the first film and the second film conforms to a preset target angle after determining the phase delay of the first film and the relative angle between the transmission directions of the polarized light detection plate and the polarized composite plate.

2. The polarizing composite sheet attachment control device according to claim 1, characterized in that: The first diaphragm comprises a combination of a linear polarizer and a polarizing beam splitter.

3. The polarizing composite sheet attachment control device according to claim 1, characterized in that: The control module is also used to calculate the transmittance of the polarizing composite sheet based on the initial light intensity and the transmitted light intensity through the polarizing composite sheet, thereby verifying whether the quality of the first film and the second film both meet the preset film quality requirements.

4. The polarizing composite sheet attachment control device according to claim 1, characterized in that: The control module is also used to calculate the phase delay of the quarter-wave plate based on the initial light intensity and the transmitted light intensity through the polarization composite plate, thereby verifying whether the quality of the second diaphragm meets the preset diaphragm quality requirements.

5. The polarizing composite sheet attachment control device according to claim 1, characterized in that: The two-degree-of-freedom adjustment mechanism includes a linear slide that can move linearly and a turntable that can rotate.

6. The polarizing composite sheet attachment control device according to claim 5, characterized in that: The support subsystem also includes a base, the two-degree-of-freedom adjustment mechanism is located at the top of the base, and the film stage is located at the top of the two-degree-of-freedom adjustment mechanism.

7. The polarizing composite sheet attachment control device according to claim 6, characterized in that: The two-degree-of-freedom adjustment mechanism is mounted on the base via a slide rail.

8. The polarizing composite sheet attachment control device according to claim 1, characterized in that: The support subsystem also includes a negative pressure generator; The membrane stage has air holes; the negative pressure generator is connected to the air holes of the membrane stage through an air pipe to create a negative pressure between the first membrane and the membrane stage.

9. The polarizing composite sheet attachment control device according to claim 1, characterized in that: The diaphragm constraint module includes two sets of opposite clamps, each set of clamps including a pair of parallel and adjustable-spaced round bars, and the two sets of clamps are used to clamp the two sides of the second diaphragm respectively.

10. The polarizing composite sheet attachment control device according to claim 1, characterized in that: The rotating mechanism includes a rotating platform, the polarizing light detector is disposed above the rotating platform, and the rotating platform has a through hole at its center for light transmission.

11. A method for controlling the attachment of a polarizing composite sheet, characterized in that: The polarizing composite sheet attachment control device as described in any one of claims 1-10 is used to achieve this, comprising the following steps: The initial light intensity of the light emitted by the light source was measured by a spectrometer when the first and second membranes were not placed. The first film to be attached is flattened and fixed using a film carrier stage; The second diaphragm to be attached is flattened and fixed by the diaphragm constraint module; The distance between the first diaphragm and the second diaphragm is adjusted using a two-degree-of-freedom adjustment mechanism; The relative angle between the light transmission directions of the first and second films is coarsely adjusted using a two-degree-of-freedom adjustment mechanism. The rotating polarizing light detector obtains the initial light intensity, transmitted light intensity, phase retardation of the first film, rotation angle of the polarizing light detector, and the relationship between the relative angles between the transmission directions of the first and second films through the measurement subsystem and control module; calculates the target rotation angle of the polarizing light detector based on the preset target angle between the transmission directions of the first and second films, and adjusts the polarizing light detector to the target rotation angle; The rotating stage is used to fine-tune the relative angle between the light transmission directions of the first and second films. At the same time, the transmitted light intensity is collected by the measurement subsystem to detect whether the actual relative angle between the light transmission directions of the first and second films meets the preset target angle; until the relative angle between the light transmission directions of the first and second films meets the preset target angle requirement. A polarizing composite sheet is obtained by attaching the second film and the first film using an attachment roller.

12. The polarization composite sheet attachment control method as described in claim 11, characterized in that: Before fine-tuning the relative angle between the light transmission directions of the first film and the second film, the following steps are also included: Based on the initial light intensity and the transmitted light intensity through the polarizing composite sheet, the transmittance of the polarizing composite sheet is calculated to determine whether the quality of the first film and the second film both meet the preset film quality requirements. If so, the process continues.

13. The polarization composite sheet attachment control method as described in claim 11, characterized in that: Before fine-tuning the relative angle between the light transmission directions of the first film and the second film, the following steps are also included: Based on the initial light intensity and the transmitted light intensity through the polarization composite sheet, the phase delay of the quarter-wave plate is calculated to verify whether the quality of the second diaphragm meets the preset diaphragm quality requirements.

Images