WO2021146959A1

WO2021146959A1 - Illumination sensor at lower part of display

Info

Publication number: WO2021146959A1
Application number: PCT/CN2020/073635
Authority: WO
Inventors: 闵丙日
Original assignee: 杭州芯格微电子有限公司
Priority date: 2020-01-21
Filing date: 2020-01-21
Publication date: 2021-07-29
Also published as: CN111670346A

Abstract

An illumination sensor (100, 101) at a lower part of a display (10, 10'), comprising: a light selection layer (200, 201) having a first light path and a second light path in which circularly polarized display light (22, 22') generated by external light (20) entered from the outside of the display (10, 10') advances and non-polarized light (30) generated by pixels advances; and a light sensor (300) having a first light receiving unit (310, 310') which detects light that has passed through the first light path, and a second light receiving unit (320, 320') which detects light that has passed through the second light path, wherein the first light path allows both the circularly polarized display light (22, 22') and the non-polarized light (30) to pass through, and the second light path blocks the circularly polarized display light (22, 22') and allows the non-polarized light (30) to pass through.

Description

Illumination sensor at the bottom of the display

Technical field

The present disclosure relates to an illuminance sensor.

Background technique

Illuminance sensors are not only used in mobile electronic devices such as mobile phones and tablet computers, but also in video electronic devices such as televisions and monitors. The illuminance sensor is a sensor that senses the brightness around the electronic device. Recently, there has been an increase in the design of displays that occupy almost the entire front surface of electronic devices. Although the size of the display becomes larger according to the requirement for a large screen, it is still necessary to ensure at least a part of the front surface to configure the camera, especially the illuminance sensor. Although the proximity sensor using ultrasonic waves can be applied to a structure where the front surface is covered by a display, it is difficult to integrate the function of sensing illuminance. On the other hand, although the illuminance sensor can also be located in an area other than the front surface, it may not be able to sense the surrounding light because of the casing used to protect the electronic device. Therefore, although the most ideal position where the illuminance sensor can be installed is the front surface of the electronic device, in a design where the display occupies the entire front surface, it is difficult to secure a position where commonly used illuminance sensors are arranged.

Summary of the invention

The purpose of the present disclosure is to provide an illuminance sensor that can be applied to an electronic device with a design that the display occupies the entire front surface.

An illuminance sensor in the lower part of the display according to an embodiment, the illuminance sensor in the lower part of the display is arranged in the lower part of the display including the pixels that generate light, the display retardation layer arranged on the upper part of the pixels, and the display polarizing layer, and the measured value is measured. The brightness of the outside of the display, wherein the illuminance sensor at the lower part of the display includes: a light selection layer having a display circularly polarized light generated by external light incident from the outside of the display and a non-polarized light generated by the pixel advances A first light path and a second light path; and a photosensor having a first light receiving portion that detects light passing through the first light path and a second light receiving portion that detects light passing through the second light path, so The first light path allows both the circularly polarized light of the display and the non-polarized light to pass, and the second light path blocks the circularly polarized light of the display and allows the non-polarized light to pass.

Preferably, the light selection layer includes: a sensor retardation layer for the circularly polarized light of the display to enter, and has an orthogonal slow axis and a fast axis; a first sensor polarization layer, located at the lower part of the sensor retardation layer, and has A polarization axis inclined at a first angle with respect to the slow axis; and a second sensor polarizing layer, which is located below the sensor delay layer and has a polarization axis inclined at a second angle with respect to the slow axis, the The sensor delay layer and the first sensor polarizing layer form the first light path, and the sensor delay layer and the second sensor polarizing layer form the second light path.

Preferably, the plurality of first sensor polarizing layers and the plurality of second sensor polarizing layers are alternately arranged on the same plane.

Preferably, the light selection layer includes: a first sensor retardation layer for the circularly polarized light of the display to enter, and has a first slow axis and a first fast axis that are orthogonal; a second sensor retardation layer for the display circle Polarized light is incident and has a second slow axis and a second fast axis orthogonal; and a sensor polarizing layer, which is located at the lower part of the first sensor retardation layer and the second sensor retardation layer, and has an angle relative to the first sensor retardation layer. The slow axis is a polarization axis inclined at a first angle, the first slow axis is orthogonal to the second slow axis, the first sensor retardation layer and the sensor polarizing layer form the first light path, the The second sensor delay layer and the sensor polarizing layer form the second light path.

Preferably, the plurality of first sensor delay layers and the plurality of second sensor delay layers are alternately arranged on the same plane.

Preferably, the light selection layer includes: a first sensor retardation layer for the circularly polarized light of the display to enter, and has a first slow axis and a first fast axis that are orthogonal; a second sensor retardation layer for the display circle Polarized light is incident and has a second slow axis and a second fast axis that are orthogonal; the first sensor polarizing layer is located at the lower part of the first sensor retardation layer and the second sensor retardation layer, and has a position relative to the first sensor retardation layer. A polarization axis with a slow axis inclined at a second angle; and a second sensor polarization layer located at the lower part of the first sensor retardation layer and the second sensor retardation layer, and having a first slow axis with respect to the first slow axis An angularly inclined polarization axis, the first slow axis is orthogonal to the second slow axis.

Preferably, a plurality of said first sensor retardation layers and a plurality of said second sensor retardation layers are alternately arranged on a first plane, and a plurality of said first sensor polarizing layers and a plurality of said second sensor polarizing layers are arranged in Alternately arranged on the second plane.

Preferably, the first light receiving unit detects linearly polarized light from a first sensor generated from the circularly polarized light of the display and a second sensor linearly polarized light generated from the non-polarized light, and the second light receiving unit detects linearly polarized light generated from the non-polarized light. The third sensor is linearly polarized.

Preferably, the light selection layer includes: a sensor retardation layer for the circularly polarized light of the display to enter, and having orthogonal slow and fast axes; and a sensor polarization layer, located at the lower part of the sensor retardation layer, and having opposite With respect to the polarization axis inclined at a second angle to the slow axis, the sensor retardation layer and the sensor polarization layer are arranged only on the upper portion of the second light-receiving part.

Preferably, the illuminance sensor at the lower part of the display further includes: a condenser lens formed on the upper surface of the light selection layer.

Preferably, the brightness of the external light after passing through the first light path is corrected by applying a proportional relationship, and the proportional relationship is that the first light path and the A proportional relationship is established between the brightness of the non-polarized light after the second light paths respectively pass.

The illuminance sensor according to the embodiment of the present disclosure can be applied to an electronic device designed such that the entire front surface is occupied by a display.

Description of the drawings

Hereinafter, the present disclosure will be described with reference to embodiments shown in the drawings. For ease of understanding, in all the drawings, the same constituent elements are denoted by the same reference numerals. The structure shown in the drawings is only an embodiment schematically shown for explaining the present disclosure, and does not limit the scope of the present disclosure. In particular, in order to facilitate the understanding of the invention, some constituent elements are shown somewhat exaggerated in the drawings. Since the drawings are for understanding the means of the invention, it should be understood that the width, thickness, etc. of the constituent elements shown in the drawings may vary in actual implementation.

FIG. 1 is a diagram for schematically explaining the working principle of the illuminance sensor at the lower part of the display;

FIG. 2 is a diagram for schematically explaining an embodiment of the light selection layer shown in FIG. 1;

FIG. 3 is a diagram for schematically explaining another embodiment of the light selection layer shown in FIG. 1;

FIG. 4 is a diagram for schematically explaining still another embodiment of the light selection layer shown in FIG. 1;

FIG. 5 is a diagram for schematically explaining still another embodiment of the light selection layer shown in FIG. 1;

FIG. 6 is an exploded perspective view for schematically illustrating an embodiment of the illuminance sensor at the lower part of the display;

FIG. 7 is an exploded perspective view for schematically illustrating another embodiment of the illuminance sensor at the lower part of the display;

FIG. 8 is an exploded perspective view for schematically illustrating still another embodiment of the illuminance sensor at the lower part of the display;

FIG. 9 is a diagram for schematically explaining the influence produced by the light generated in the display;

10 is a diagram for schematically explaining an embodiment of an illuminance sensor in the lower part of the display that can reduce the influence of light generated in the display;

11 is a diagram for schematically explaining another embodiment of an illuminance sensor in the lower part of the display capable of reducing the influence of light generated in the display;

FIG. 12 is a diagram for schematically explaining another working principle of the illuminance sensor at the lower part of the display;

FIG. 13 is an exploded perspective view for schematically explaining the illuminance sensor at the lower part of the display operating according to the working principle shown in FIG. 12.

Detailed ways

The present disclosure can incorporate various modifications and can have various embodiments. Specific embodiments are shown in the drawings and described in detail. It should be understood that this does not limit the present disclosure to specific embodiments, but includes all modifications, equivalents, and alternatives that fall within the concept and technical scope of the present disclosure. In particular, the functions, features, and embodiments described below with reference to the drawings can be implemented alone or in combination with another embodiment. Therefore, it should be noted that the scope of the present disclosure is not limited to the manner shown in the drawings.

On the other hand, with regard to the terms used in this specification, expressions such as "substantially", "almost", "about", etc. are expressions that take into consideration allowable margins or possible errors in actual implementation. For example, "substantially 90 degrees" should be interpreted as including angles that can obtain the same effects as those at 90 degrees. For another example, "almost none" should be interpreted as including to the extent that even if there is a little, it can be ignored.

On the other hand, unless specifically mentioned, “side” or “horizontal” is used to indicate the left-right direction in the drawings, and “vertical” is used to indicate the up-down direction in the drawings. In addition, unless specifically defined, the angle, incident angle, etc. are based on a virtual straight line perpendicular to the horizontal plane shown in the drawing.

In all the drawings, the same or similar elements are referenced using the same reference numerals.

FIG. 1 is a diagram for schematically explaining the operating principle of the illuminance sensor at the lower part of the display.

The illuminance sensor 100 at the lower part of the display is arranged at the lower part of the display 10. The display 10 includes a pixel layer 13 formed with a plurality of pixels P that generate light, a display polarizing layer 11 and a display retardation layer 12 laminated on top of the pixel layer 13. In order to protect the display polarizing layer 11, the display retardation layer 12, and the pixel layer 13, a protective layer formed of an opaque material such as metal or synthetic resin may be disposed on the bottom surface of the display 10. As an embodiment, the illuminance sensor 100 at the lower part of the display composed of the light selection layer 200 and the light sensor 300 may be arranged in a region where a part of the protective layer is removed (hereinafter referred to as a completed structure). As another embodiment, the light selection layer 200 of the illuminance sensor 100 at the lower part of the display may be manufactured into a film shape and laminated on the bottom surface of the display 10. The illuminance sensor at the lower part of the display can be realized in a manner that the light sensor 300 is attached to the bottom surface of the light selection layer 200 (hereinafter referred to as an assembled structure). Hereinafter, in order to avoid repetitive description, the description will be centered on the completed structure.

The display polarizing layer 11 and the display retardation layer 12 can improve the visibility of the display 10. The external light 20 incident through the upper surface of the display 10 is unpolarized light. If the external light 20 is incident on the upper surface of the display polarizing layer 11, only the linearly polarized light 21 of the display substantially consistent with the polarization axis of the display polarizing layer 11 passes through the display polarizing layer 11. When the display linearly polarized light 21 passes through the display retardation layer 12, it becomes the display circularly polarized light 22 (or elliptical polarized light) rotating in the clockwise direction or the counterclockwise direction. If the display circularly polarized light 22 is reflected on the pixel layer 13 and is incident on the display retardation layer 12 again, it becomes the second linearly polarized light. Here, if the polarization axis of the display retardation layer 12 is inclined by about 45 degrees with respect to the slow axis, the polarization axis of the linear polarization 21 of the display and the polarization axis of the second linear polarization are orthogonal to each other. Therefore, the second linearly polarized light, that is, the external light reflected by the pixel layer 13 is blocked by the display polarizing layer 11 and cannot be emitted to the outside of the display. As a result, the visibility of the display 10 can be improved.

The unpolarized light 30 generated by the pixel P advances not only toward the upper surface of the display 10 but also toward the bottom surface. In addition, a part of the non-polarized light 30 that travels toward the upper surface is reflected inside the display 10 and travels toward the bottom surface again. Different from the display circularly polarized light 22, the non-polarized light 30 directly passes through the display retardation layer 12, is converted into linearly polarized light by the display polarizing layer 11, and is emitted to the outside.

The illuminance sensor 100 at the lower part of the display includes a light selection layer 200 having two light paths, and a light sensor 300 that detects light passing through each light path. The light incident on the illuminance sensor 100 at the lower part of the display is the display circularly polarized light 22 generated from the external light 20 and the non-polarized light 30 generated inside the display. The first light path and the second light path in the light selection layer 200 function in different ways for the circularly polarized light 22 and the non-polarized light 30 of the display. The first light path allows both the circularly polarized light 22 and the non-polarized light 30 of the display to pass. On the contrary, the second light path passes the non-polarized light 30 and substantially blocks the circularly polarized light 22 of the display. The display circularly polarized light 22 after passing through the first light path becomes the first sensor linearly polarized light 23, and the unpolarized light 30 after passing through the first light path and the second light path becomes the second sensor linearly polarized light 31 and the third sensor linearly polarized light 32.

The photosensor 300 includes a first light receiving part 310 corresponding to the first light path and a second light receiving part 320 corresponding to the second light path. For example, the first light receiving section 310 generates a first pixel current that is substantially proportional to the amount of light of the circularly polarized light 22 and non-polarized light 30 of the display, and the second light receiving section 320 generates a second pixel current that is substantially proportional to the amount of light of the non-polarized light 30. . The

light receiving unit

310 or 320 may be composed of, for example, one photodiode or a plurality of photodiodes (hereinafter referred to as PD array). As an embodiment, one or two photodiodes may correspond to one pixel P. As another embodiment, the PD array may correspond to 1 pixel P. As yet another embodiment, one or two photodiodes may correspond to multiple pixels P. As yet another embodiment, the PD array may correspond to a plurality of pixels P. Here, the first light receiving unit 310 and the second light receiving unit 320 can detect light belonging to a specific wavelength range together, or separately detect light belonging to different wavelength ranges, such as red, green, cyan, near infrared, and the like.

The illuminance sensor is a device used to measure the brightness of external light. When the illuminance sensor is arranged in the lower part of the display, not only the external light passing through the display, but also the light generated inside the display is incident on the illuminance sensor. Therefore, in order to accurately measure the brightness of external light, it is necessary to measure the brightness of light generated inside the display. If only the brightness of the light generated inside the display can be measured, the brightness of the external light measured by this can be corrected.

As described above, the second sensor linearly polarized light 31 and the third sensor linearly polarized light 32 generated from the non-polarized light 30 can be detected by the first light receiving section 310 and the second light receiving section 320, respectively. In particular, since the light selection layer 200 prevents the linearly polarized light generated from the display circularly polarized light 22 from being substantially incident on the second light receiving section 320, the second light receiving section 320 can only measure the third sensor linearly polarized light generated from the non-polarized light 30. 32 brightness. On the other hand, the brightness of the second sensor linear polarization 31 and the third sensor linear polarization 32 can be substantially the same, on the contrary, they can also be different, which will be described in detail below. However, since the linearly polarized light 31 of the second sensor and the linearly polarized light 32 of the third sensor are generated from the unpolarized light 30 generated by one or more pixels, a linear proportional relationship or a non-linear proportional relationship is established for the brightness between the two. . The non-linear proportional relationship may be caused by various reasons such as the structural feature of the display 10, the difference in the pixel area corresponding to each light receiving unit, and the wavelength range of the non-polarized light 30. The proportional relationship between the linear polarization of the second sensor 31 and the linear polarization of the third sensor 32 can be measured in an environment that is not affected by the external light 20. Based on the proportional relationship, the degree to which the second sensor linear polarization 31 contributes to the brightness measured by the first light receiving unit 310 can be calculated from the brightness of the third sensor linear polarization 32 measured by the second light receiving unit 320. As a result, the brightness of the external light 20 can be accurately measured.

Hereinafter, in all the drawings, the hatching shown in the retardation layer indicates the direction of the slow axis, and the hatching shown in the polarizing layer schematically indicates the direction of the polarization axis with respect to the slow axis extending in the horizontal direction. On the other hand, it is shown that the slow axis of the display retardation layer and the slow axis of the sensor retardation layer both extend in the horizontal direction, or the slow axis of the display retardation layer and the slow axis of the sensor retardation layer extend in the vertical direction. This is simply expressed to facilitate understanding. It should be understood that it is not necessary to align the slow axis of the sensor retardation layer with the slow axis of the display retardation layer. On the other hand, in order to simplify the drawing, as for the unpolarized light emitted from the pixel P, only the light emitted through the light selection layer is shown.

FIG. 2 is a diagram for schematically explaining an embodiment of the light selection layer shown in FIG. 1.

The light selection layer 200 includes a sensor retardation layer 210, a first sensor polarizing layer 220 and a second sensor polarizing layer 225. The sensor delay layer 210 is disposed on the upper part of the first sensor polarizing layer 220 and the second sensor polarizing layer 225, and the photosensor 300 is disposed on the lower part of the first sensor polarizing layer 220 and the second sensor polarizing layer 225. The first light receiving unit 310 of the photosensor 300 is arranged under the first sensor polarizing layer 220, and the second light receiving unit 320 is arranged under the second sensor polarizing layer 225. As an example, the light selection layer 200 can be manufactured by laminating (laminating) the sensor retardation layer 210 on the upper surfaces of the first sensor polarizing layer 220 and the second sensor polarizing layer 225. The light selection layer 200 may be attached to the bottom surface of the display 10. The light sensor 300 may be attached to the bottom surface of the light selection layer 200. As another embodiment, the light sensor 300 may be realized by a thin film transistor. Thus, the illuminance sensor 100 in the lower part of the display can be manufactured by laminating the film-shaped sensor retardation layer 210, the first and second

sensor polarizing layers

220 and 225, and the photosensor 300.

The polarization axis of the first sensor polarization layer 220 and the polarization axis of the second sensor polarization layer 225 are inclined at different angles with respect to the slow axis of the sensor delay layer 210. The polarization axis of the first sensor polarizing layer 220 may be inclined at a first angle, for example +45 degrees, with respect to the slow axis of the sensor retardation layer 210, and the polarization axis of the second sensor polarizing layer 225 may be tilted at a first angle with respect to the slow axis of the sensor retardation layer 210. Two angles such as -45 degrees inclination.

The first light receiving unit 310 of the photosensor 300 detects the first sensor linearly polarized light 23 and the second sensor linearly polarized light 31 emitted from the first sensor polarizing layer 220, and the second light receiving unit 320 detects the third light emitting from the second sensor polarizing layer 225. The sensor is linearly polarized 32. The

light receiving units

310 and 320 can generate a pixel current having a magnitude corresponding to the amount of light detected. The

light receiving parts

310 and 320 are, for example, photodiodes, but are not limited to this.

Next, the operation of the illuminance sensor 100 at the lower part of the display having the light selection layer 200 having the above-mentioned structure will be described.

The display circularly polarized light 22 and non-polarized light (not shown in FIG. 2, 30 in FIG. 1) are incident on the upper surface of the light selection layer 200, that is, the upper surface of the sensor retardation layer 210. The display circularly polarized light 22 is light after the external light 20 has passed through the display polarizing layer 11 and the display retardation layer 12, and the non-polarized light 30 is light traveling downward from the pixel P toward the light selection layer 200.

The display polarizing layer 11 may have a polarizing axis inclined at a second angle, for example -45 degrees, with respect to the slow axis of the display retardation layer 12. Therefore, the linearly polarized light 21 of the display after passing through the display polarizing layer 11 may be incident at a second angle with respect to the slow axis of the display retardation layer 12. If the first polarized part of the display linear polarizer 21 transmitted along the fast axis and the second polarized part of the display linear polarized light 21 transmitted along the slow axis pass through the display retardation layer 12, a phase difference of λ/4 will occur between each other. Thus, the linearly polarized light 21 of the display after passing through the display retardation layer 12 can become the circularly polarized light 22 of the display rotating in the counterclockwise direction.

The display circularly polarized light 22 having a phase difference of λ/4 between the fast axis and the slow axis becomes the sensor internal linearly polarized light 22a through the sensor delay layer 210. The polarization axis of the linear polarization 22a inside the sensor and the polarization axis of the display linear polarization 21 are orthogonal to each other. On the other hand, the non-polarized light 30 directly passes through the sensor retardation layer 210.

Since the polarization axis of the first sensor polarization layer 220 is substantially parallel to the polarization axis of the sensor internal linear polarization 22a, the sensor internal linear polarization 22a emitted from the sensor delay layer 210 can pass through the first sensor polarization layer 220. On the contrary, since the polarization axis of the second sensor polarization layer 225 is substantially perpendicular to the polarization axis of the internal linear polarization 22a of the sensor, the internal linear polarization 22a of the sensor can be blocked by the second sensor polarization layer 225. On the other hand, the unpolarized light 30 emitted from the sensor delay layer 210 passes through the first sensor polarizing layer 220 and the second sensor polarizing layer 225 to become the second sensor linearly polarized light 31 and the third sensor linearly polarized light 32 respectively. That is, the first light receiving unit 310 can detect the first sensor linearly polarized light 23 and the second sensor linearly polarized light 31 through the first light path constituted by the sensor delay layer 210-first sensor polarizing layer 220, and the sensor delay layer 210- The second light path formed by the second sensor polarizing layer 225, and the second light receiving unit 320 can detect the linear polarized light 32 of the third sensor.

Fig. 3 is a diagram for schematically explaining another embodiment of the light selection layer shown in Fig. 1.

The light selection layer 201 includes a first sensor retardation layer 230, a second sensor retardation layer 235, and a sensor polarization layer 240. The first sensor delay layer 230 and the second sensor delay layer 235 are arranged on the upper part of the sensor polarizing layer 240, and the photosensor 300 is arranged on the lower part of the sensor polarizing layer 240. The first light receiving portion 310 of the photosensor 300 is arranged at a position where the light emitted from the first sensor retardation layer 230 passes through the sensor polarizing layer 240, and the second light receiving portion 320 is arranged where the light emitted from the second sensor retardation layer 235 passes through The position reached after the sensor polarizing layer 240. As an embodiment, the light selective layer 201 may be manufactured by laminating the first sensor retardation layer 230 and the second sensor retardation layer 235 on the upper surface of the sensor polarizing layer 240. The light selection layer 201 may be attached to the bottom surface of the display 10. The light sensor 300 may be attached to the bottom surface of the light selection layer 201. As another embodiment, the light sensor 300 may be realized by a thin film transistor. Thus, the illuminance sensor 100 at the lower part of the display can be manufactured by laminating the film-like first and second sensor retardation layers 230 and 235, the sensor polarizing layer 240, and the photosensor 300.

The slow axis of the first sensor delay layer 230 and the slow axis of the second sensor delay layer 235 are substantially orthogonal. The polarization axis of the sensor polarizing layer 240 may be inclined at a first angle, such as +45 degrees, with respect to the slow axis of the first sensor retardation layer 230, or may be inclined at a second angle, such as −45 degrees, with respect to the slow axis of the second sensor retardation layer 235. tilt.

The first light receiving part 310 of the photosensor 300 is located at the vertical lower part of the first sensor delay layer 230 and detects the first sensor linear polarized light 23 and the second sensor emitted after the display circularly polarized light 22 passes through the first sensor delay layer 230 and the sensor polarizing layer 240 Linear polarization 31. The second light receiving part 320 of the photosensor 300 is located at the vertical lower part of the second sensor delay layer 235 and detects the linear polarization 32 of the third sensor. The

light receiving units

light receiving parts

310 and 320 may be photodiodes, for example, but are not limited thereto.

Next, the operation of the illuminance sensor 100 at the lower part of the display having the light selection layer 201 of the above-mentioned structure will be described. The description of the circularly polarized light 22 and the non-polarized light 30 of the display is the same as that of FIG. 2, so the description is omitted.

The display circularly polarized light 22 and non-polarized light (not shown in FIG. 3, 30 in FIG. 1) are incident on the upper surface of the light selection layer 201, that is, the upper surfaces of the first sensor retardation layer 230 and the second sensor retardation layer 235. The display circularly polarized light 22 having a phase difference of λ/4 between the fast axis and the slow axis becomes the first sensor internal linear polarization 22b through the first sensor delay layer 230, and becomes the second sensor internal linear light through the second sensor delay layer 235 Polarized light 22c. Since the slow axis of the first sensor delay layer 230 is orthogonal to the slow axis of the second sensor delay layer 235, the polarization axis of the linear polarization 22b inside the first sensor and the polarization axis of the linear polarization 22c inside the second sensor can also be orthogonal. Specifically, the display circularly polarized light 22 having a phase difference of λ/4 between the first polarized part and the second polarized part passes through the first sensor retardation layer 230 to eliminate the phase difference, so that it can become a polarized light having a linearly polarized light 21 with respect to the display. The axis is substantially parallel to the polarization axis inside the first sensor linearly polarized light 22b. On the contrary, the display circularly polarized light 22 is increased by a phase difference of λ/4 through the second sensor retardation layer 235, so that it can become the second sensor internal linear polarized light 22c having a polarization axis perpendicular to the polarization axis of the display linear polarization 21. On the other hand, the unpolarized light 30 directly passes through the first and second sensor retardation layers 230 and 235.

Although the first sensor internal linear polarization 22b emitted from the first sensor delay layer 230 passes through the sensor polarization layer 240, the second sensor internal linear polarization 22c emitted from the second sensor delay layer 235 cannot pass through the sensor polarization layer 240. The sensor polarization layer 240 has a polarization axis inclined at a first angle, for example -45 degrees, with respect to the slow axis of the first sensor retardation layer 230, or has a second angle, such as +45 degrees, with respect to the slow axis of the second sensor delay layer 235. Tilted polarization axis. Therefore, the polarization axis of the linear polarization 22b inside the first sensor is substantially parallel to the polarization axis of the sensor polarization layer 240, so the internal linear polarization 22b of the first sensor can pass through the sensor polarization layer 240 almost without loss. On the contrary, the polarization axis of the linear polarization 22c inside the second sensor is substantially perpendicular to the polarization axis of the sensor polarization layer 240, so the internal linear polarization 22c of the second sensor can be blocked by the sensor polarization layer 240. In addition, the unpolarized light 30 after passing through the first sensor retardation layer 230 and the second sensor retardation layer 235 passes through the sensor polarizing layer 240 to become the second sensor linearly polarized light 31 and the third sensor linearly polarized light 32. That is, the first light receiving unit 310 can detect the first sensor linear polarization 23 and the second sensor linear polarization 31 through the first light path constituted by the first sensor delay layer 230 and the sensor polarization layer 240. In addition, the second light receiving unit 320 can detect the third sensor linearly polarized light 32 through the second light path composed of the second sensor delay layer 235 and the sensor polarizing layer 240.

Fig. 4 is a diagram for schematically explaining still another embodiment of the light selection layer shown in Fig. 1. In FIG. 4, the structure of the light selection layer 200 is the same as that of FIG. 2, and the polarization axis of the display polarization layer 11' of the display 10' is different from the polarization axis of the display polarization layer 11 of FIG. The description overlapping with FIG. 2 is omitted, and the operation of the illuminance sensor 100 at the lower part of the display will be described.

The display polarizing layer 11' may have a polarizing axis inclined at a first angle, for example +45 degrees, with respect to the slow axis of the display retardation layer 12. Therefore, the linearly polarized light 21 of the display after passing through the display polarizing layer 11' can be incident at a first angle with respect to the slow axis of the display retardation layer 12. If the first polarized part of the linear polarized light 21 of the display transmitted along the fast axis and the second polarized part of the linear polarized light 21 of the display transmitted along the slow axis pass through the display retardation layer 12, a phase difference of λ/4 will occur between each other. . Thus, the linearly polarized light 21 of the display after passing through the display retardation layer 12 can become the circularly polarized light 22' of the display rotating in the clockwise direction.

The display circularly polarized light 22' having a phase difference of λ/4 between the fast axis and the slow axis passes through the sensor retardation layer 210 to become the sensor internal linearly polarized light 22d. The polarization axis of the linear polarization 22d inside the sensor and the polarization axis of the display linear polarization 21 are orthogonal to each other. On the other hand, the non-polarized light 30 directly passes through the sensor retardation layer 210.

The polarization axis of the first sensor polarization layer 220 is perpendicular to the polarization axis of the internal linear polarization 22d of the sensor. Therefore, the internal linear polarization 22d of the sensor emitted from the sensor delay layer 210 can be blocked by the first sensor polarization layer 220. On the contrary, the polarization axis of the second sensor polarization layer 225 is substantially parallel to the polarization axis of the linear polarization 22d inside the sensor, so the linear polarization 22d inside the sensor can pass through the second sensor polarization layer 225. On the other hand, the unpolarized light 30 emitted from the sensor delay layer 210 passes through the first sensor polarizing layer 220 and the second sensor polarizing layer 225 to become the second sensor linearly polarized light 31 and the third sensor linearly polarized light 32 respectively. That is, the first light receiving unit 320' can detect the first sensor linear polarization 23' and the third sensor linear polarization 32 through the first light path constituted by the sensor delay layer 210 and the second sensor polarization layer 225. On the other hand, the second light receiving portion 310' can detect the second sensor linearly polarized light 31 through the second light path constituted by the sensor delay layer 210 and the first sensor polarizing layer 220.

Fig. 5 is a diagram for schematically explaining still another embodiment of the light selection layer shown in Fig. 1. In FIG. 5, the structure of the light selection layer 201 is the same as that of FIG. 3, and the polarization axis of the display polarization layer 11' of the display 10' is different from the polarization axis of the display polarization layer 11 of FIG. The description overlapping with FIG. 3 is omitted, and the operation of the illuminance sensor 100 at the lower part of the display will be described.

The display circularly polarized light 22' and non-polarized light (not shown in FIG. 5, 30 in FIG. 1) rotating in the clockwise direction are directed toward the upper surface of the light selection layer 201 (ie, the first sensor retardation layer 230 and the second sensor The upper surface of the retardation layer 235) is incident. The display circularly polarized light 22' with a phase difference of λ/4 between the fast axis and the slow axis passes through the first sensor delay layer 230 to become the first sensor internal linear polarization 22e, and through the second sensor delay layer 235 to become the second sensor internal Linear polarized light 22f. The slow axis of the first sensor delay layer 230 is orthogonal to the slow axis of the second sensor delay layer 235, so the polarization axis of the linear polarization 22e inside the first sensor and the polarization axis of the linear polarization 22f inside the second sensor can also be orthogonal. Specifically, the display circularly polarized light 22' having a phase difference of λ/4 between the first polarized part and the second polarized part passes through the first sensor retardation layer 230 to increase the phase difference of λ/4, so that it can become The linear polarization axis of the display linear polarization 21 is perpendicular to the polarization axis and the internal linear polarization 22e of the first sensor. In contrast, the display circularly polarized light 22' passes through the second sensor retardation layer 235 to cancel the λ/4 phase difference, and can become the second sensor internal linear polarized light 22f having a polarization axis substantially parallel to the polarization axis of the display linear polarization 21. On the other hand, unpolarized light directly passes through the first sensor retardation layer 230 and the second sensor retardation layer 235.

Although the first sensor internal linear polarization 22e emitted from the first sensor delay layer 230 cannot pass through the sensor polarization layer, the second sensor internal linear polarization 22f emitted from the second sensor delay layer 235 can pass through the sensor polarization layer 240. The sensor polarization layer 240 has a polarization axis inclined at a first angle, for example +45 degrees, with respect to the slow axis of the first sensor delay layer 230, or has a second angle, such as -45 degrees, with respect to the slow axis of the second sensor delay layer 235. Tilted polarization axis. Therefore, the polarization axis of the linear polarization 22e inside the first sensor is substantially perpendicular to the polarization axis of the sensor polarization layer 240, so the internal linear polarization 22e of the first sensor can be blocked by the sensor polarization layer 240. On the contrary, the polarization axis of the linear polarization 22f inside the second sensor is substantially parallel to the polarization axis of the sensor polarization layer 240, so the internal linear polarization 22f of the second sensor can pass through the sensor polarization layer 240 almost without loss. On the other hand, the unpolarized light 30 after passing through the first sensor retardation layer 230 and the second sensor retardation layer 235 passes through the sensor polarizing layer 240 to become the second sensor linearly polarized light 31 and the third sensor linearly polarized light 32. That is, the first light receiving unit 320' can detect the first sensor linear polarization 23' and the third sensor linear polarization 32 through the first light path constituted by the second sensor delay layer 235-the sensor polarization layer 240. On the other hand, the second light receiving portion 310' can detect the second sensor linearly polarized light 31 through the second light path composed of the first sensor delay layer 230 and the sensor polarizing layer 240.

Fig. 6 is an exploded perspective view for schematically explaining an embodiment of the illuminance sensor at the lower part of the display.

As described above, the illuminance sensor 10 at the lower part of the display can be manufactured by laminating the film-shaped sensor retardation layer 202, the sensor polarizing layer 203, and the photosensor 300. The sensor delay layer 202 may be formed to be substantially parallel to the slow axis on the entire surface.

The sensor polarizing layer 203 may be formed by alternately arranging the first sensor polarizing layer 220 and the second sensor polarizing layer 225 having different polarization axes. The first sensor polarizing layer 220 and the second sensor polarizing layer 225 may have a rectangular shape extending in one direction. Wherein, the polarization axis of the first sensor polarization layer 220 may be inclined at a first angle with respect to the slow axis of the sensor delay layer 202, and the polarization axis of the second sensor polarization layer 225 may be at a second angle with respect to the slow axis of the sensor delay layer 202. tilt.

The optical sensor 300 is composed of a plurality of light receiving

units

310 and 320. The plurality of light receiving

units

310 and 320 output pixel currents corresponding to the amount of incident light. The first light-receiving part 310 and the second light-receiving part 320 are substantially the same light-receiving part. The first light-receiving part 310 located at the position where light with a relatively large amount of light is incident is denoted as "B", and the light-receiving portion at a position with a relatively small amount of light The second light receiving part 320 at the position where the light is incident is indicated as "D".

Since the first sensor polarizing layer 220 allows the first sensor linearly polarized light and the second sensor linearly polarized light to pass (that is, the first light path), the first light receiving portion 310 is arranged along the length direction of the first sensor polarizing layer 220 in the first A lower part of the sensor polarizing layer 220. On the contrary, since the second sensor polarizing layer 225 only allows the third sensor to pass linearly polarized light (that is, the second light path), the second light receiving part 320 is arranged along the length direction of the second sensor polarizing layer 220 in the second sensor polarized light. The lower part of layer 225.

FIG. 7 is an exploded perspective view for schematically explaining another embodiment of the illuminance sensor in the lower part of the display.

The sensor polarizing layer 203 may be formed by alternately arranging the first sensor polarizing layer 220 and the second sensor polarizing layer 225 having different polarization axes. The first sensor polarizing layer 220 and the second sensor polarizing layer 225 may have a rectangular shape. Therefore, the sensor polarizing layer 203 may have the following structure: each side of the first sensor polarizing layer 220 is in contact with the four second sensor polarizing layers 225, or each side of the second sensor polarizing layer 225 is in contact with the four first sensor polarizing layers 220 get in touch with. Wherein, the polarization axis of the first sensor polarization layer 220 may be inclined at a first angle with respect to the slow axis of the sensor delay layer 202, and the polarization axis of the second sensor polarization layer 225 may be at a second angle with respect to the slow axis of the sensor delay layer 202. tilt.

Since the first sensor polarizing layer 220 passes the first sensor linearly polarized light and the second sensor linearly polarized light (that is, the first light path), the first light receiving part 310 is arranged under the first sensor polarizing layer 220. In contrast, since the second sensor polarizing layer 225 only allows the third sensor to pass linearly polarized light (that is, the second light path), the second light receiving section 320 is arranged at the lower portion of the second sensor polarizing layer 225. Therefore, the planar arrangement structure of the first light receiving part 310 and the second light receiving part 320 may be substantially the same as the sensor polarizing layer 203.

Fig. 8 is an exploded perspective view for schematically explaining still another embodiment of the illuminance sensor at the lower part of the display.

The sensor delay layer 202 may be formed by alternately arranging the first sensor delay layer 230 and the second sensor delay layer 235 having slow axes that are substantially perpendicular to each other. The first sensor delay layer 230 and the second sensor delay layer 235 have rectangular shapes extending in the first direction.

The sensor polarizing layer 203 may be formed by alternately arranging the first sensor polarizing layer 220 and the second sensor polarizing layer 225 having different polarization axes. The first sensor polarizing layer 220 and the second sensor polarizing layer 225 may have a rectangular shape extending in a second direction orthogonal to the first direction. Wherein, the polarization axis of the first sensor polarization layer 220 may be inclined at a second angle with respect to the slow axis of the first sensor delay layer 230, and the polarization axis of the second sensor polarization layer 225 may be relative to the slow axis of the first sensor delay layer 230 Tilt at the first angle.

The first sensor delay layer 230-the second sensor polarizing layer 225 and the second sensor delay layer 235-the first sensor polarizing layer 220 are the first light paths through which the linearly polarized light of the first sensor and the linearly polarized light of the second sensor pass. The first sensor delay layer 230-the first sensor polarizing layer 220 and the second sensor delay layer 235-the second sensor polarizing layer 225 are the second light paths through which only the linearly polarized light of the third sensor passes. Therefore, the planar arrangement structure of the first light receiving section 310 and the second light receiving section 320 may have the following structure: each side of the first light receiving section 310 is in contact with the four second light receiving sections 320, or each side of the second light receiving section 320 is in contact with the four second light receiving sections 320. The four first light receiving parts 310 are in contact.

FIG. 9 is a diagram for schematically explaining the influence caused by the light generated in the display. For simplicity, the light selection layer (200 or 201) is omitted in FIG. 8.

The first light receiving unit 310 and the second light receiving unit 320 of the photosensor 300 need to detect light passing through the same position or area on the bottom surface of the display 10.

In order to emit light from the same position on the bottom surface of the display 10, a pair of light-receiving parts (ie, the first light-receiving part 310 and the second light-receiving part 320) may be configured to correspond to one pixel P on the pixel layer 13 of the display 10. correspond. In this structure, due to the pitch between the pixels P on the pixel layer 13, the area of the first light receiving portion 310 and the second light receiving portion 320 may be relatively small. Therefore, the sensitivity of the first light receiving section 310 and the second light receiving section 320 needs to be relatively high compared to the structure described below. The first light receiving unit 310 and the second light receiving unit 320 detect _{the light generated by the same pixel PG} . Therefore, in the absence of external light, the light amount of the linearly polarized light of the second sensor and the light amount of the linearly polarized light of the third sensor may be substantially the same. It should be noted that in this structure, due to reflections in the interior of the display 10, the amount of linearly polarized light of the second sensor and the amount of linearly polarized light of the third sensor may also be different.

The _{amount of light generated by the pixel PG} may vary depending on the image being displayed on the display 10. However, since the first light receiving unit 310 and the second light receiving unit 320 detect _{the light generated by the same pixel PG} , it is possible to easily derive the proportional relationship between the amount of linearly polarized light of the second sensor and the amount of linearly polarized light of the third sensor.

Similarly, a pair of light receiving parts can detect light emitted from the same area on the bottom surface of the display 10. In this structure, the area of the first light receiving portion 310 and the second light receiving portion 320 can be relatively large compared to a structure that detects light emitted from the same pixel. Therefore, the sensitivity of the first light receiving section 310 and the second light receiving section 320 may be relatively low compared to the above-mentioned structure. The lower end of FIG. 9, the first portion 310 and the second light 320 may detect light receiving portion together emitted from the pixel P _B and P _R by pixel. The first light receiving portion 310 may also be positioned to detect light from the left pixel P _B, P _Gl emitted second light receiving unit may further detect the light from the pixel P located at the right side _R P _G2 emitted. The light generated by the pixels located outside the same area will affect the proportional relationship between the linearly polarized light amount of the second sensor and the linearly polarized light amount of the third sensor.

FIG. 10 is a diagram for schematically explaining an embodiment of an illuminance sensor in the lower part of the display capable of reducing the influence of light generated in the display.

10, in the illuminance sensor 100 at the lower part of the display, the light sensor 300 may include first

light receiving parts

310a, 310b, 310c and second

light receiving parts

320a, 320b, 320c that are alternately arranged. The pixels P4, P5, and P6 are shared by the first light receiving section 310b and the second light receiving section 320b. The pixels P2, P3, and P4 are shared by the second light receiving section 320a and the first light receiving section 310b. The pixels P6, P7, P8 are in the second light receiving section 310b. The second light receiving portion 320b and the first light receiving portion 310c are common. In this way, the proportional relationship among the four

light receiving parts

320a, 310b, 320b, and 310c can be calculated. As a result, it is possible to substantially reduce or eliminate the influence of light emitted from pixels located outside the same area.

FIG. 11 is a diagram for schematically explaining another embodiment of the illuminance sensor in the lower part of the display capable of reducing the influence of light generated in the display.

Referring to FIG. 11, the illuminance sensor 100 at the lower part of the display may further include a condenser lens 240 at the upper part of the light selection layer 200. The condenser lens 240 condenses the light emitted from the same area on the pixel layer 13 toward the first light receiving portion 310 and the second light receiving portion 320. Thereby, the light emitted from the same area is averaged and reaches the first light receiving section 310 and the second light receiving section 320. As a result, the influence of light generated by a specific pixel can be reduced. In addition, due to the condenser lens 240, the area of the same area will be relatively increased, so the influence of the light emitted from the pixels located outside the same area can be substantially reduced or eliminated. On the other hand, the amount of light incident on the photosensor 300 increases, so that the influence of the sensitivity of the light receiving unit can be reduced.

FIG. 12 is a diagram for schematically explaining the operation of the illuminance sensor in the lower part of the display. The description overlapping with FIG. 1 is omitted, and the description will be centered on the difference.

The illuminance sensor 101 at the lower part of the display is arranged at the lower part of the display 10. The illuminance sensor 101 at the lower part of the display includes a light selection layer 200 having two light paths and a light sensor 300 that detects light passing through each light path. The light incident on the illuminance sensor 101 at the lower part of the display is the display circularly polarized light 22 generated from the external light 20 and the non-polarized light 30 generated inside the display.

The first light path and the second light path in the light selection layer 200 play different roles for the circularly polarized light 22 and the non-polarized light 30 of the display. The first light path allows the circularly polarized light 22 and the non-polarized light 30 of the display to pass. The display circularly polarized light 22 and the non-polarized light 30 after passing through the first light path reach the first light receiving unit 310. On the contrary, as an example, the second light path allows the non-polarized light 30 to pass and substantially blocks the circularly polarized light 22 of the display. The unpolarized light 30 that has passed through the second optical path becomes the third sensor linearly polarized light 32 and reaches the second light receiving unit 320. As another example, the second light path allows the non-polarized light 30 to pass and a part of the polarized light 23' of the circularly polarized light 22 of the display. The display circularly polarized light 22 generated from the external light 20 may enter the illuminance sensor 101 at the lower part of the display through various paths. For example, the external light 20 itself can enter the interior of the display 10 at a variety of incident angles, or through reflection in the interior of the display 10, the incident angle to the illuminance sensor 101 at the lower part of the display can be various. Thus, a part of the polarized light 23' of the circularly polarized light 22 of the display can be detected by the second light receiving unit 320. Part of the polarized light 23' of the display circularly polarized light 22 detected by the second light receiving unit 320 is proportional to the light amount of the display circularly polarized light 22 detected by the first light receiving unit 310, or has a substantially constant light amount.

In an embodiment, the circularly polarized light 22 and the non-polarized light 30 of the display may be detected by the first light receiving part 310, and the linearly polarized light 32 of the third sensor may be detected by the second light receiving part 320. In the second light receiving section 320, since the light selection layer 200 does not enter the linearly polarized light generated by the display circularly polarized light 22, the second light receiving section 320 can only measure the brightness of the third sensor linearly polarized light 32 generated from the non-polarized light 30. The first proportional relationship is established between the brightness of the display circularly polarized light 22 and the brightness of the external light 20, and the second proportional relationship is established between the non-polarized light 30 and the third sensor linearly polarized light 32. The first proportional relationship and the second proportional relationship may be linear or non-linear. The first proportional relationship may be determined according to the measurement result when all pixels of the display 10 are turned off. The second proportional relationship It can be determined based on a measurement result in a state where the pixels of the display 10 are turned on in a state where there is no external light 20. After the brightness detected by the first light receiving unit 310 is corrected by the second proportional relationship, the first proportional relationship may be applied to the corrected brightness, so that the brightness of the external light 20 can be determined.

In addition, in another embodiment, the display circularly polarized light 22 and the non-polarized light 30 can be detected by the first light receiving unit 310, and the third sensor linearly polarized light 32 and a part of the polarized light 23' of the display circularly polarized light 22 can be detected by the second light receiving unit 320. . The first proportional relationship is established between the brightness of the display circularly polarized light 22, the brightness of the external light 20, and the brightness of a part of the polarized light 23', and the second proportional relationship is established between the non-polarized light 30 and the third sensor linearly polarized light 32. Among them, if the brightness of a part of the polarized light 23' is negligibly small, the brightness of a part of the polarized light 23' can be excluded in the first proportional relationship. On the other hand, in the case where the brightness of the external light 20 is substantially constant even though it changes, the brightness of a part of the polarized light 23' can be used to correct the brightness of the linear polarized light 32 of the third sensor.

FIG. 13 is an exploded perspective view for schematically explaining the illuminance sensor at the lower part of the display operating according to the operating principle shown in FIG. 12.

As described above, the illuminance sensor 10 at the lower part of the display can be manufactured by laminating the film-shaped sensor retardation layer 210, the sensor polarizing layer 225, and the photosensor 300.

The sensor delay layer 210 may be formed to be substantially parallel to the slow axis on the entire surface. In addition, the first light transmission layer 211 may be formed on the same plane as the sensor retardation layer 210. The first light transmitting layer 211 is laminated on the upper portion of the first light receiving portion 310 of the photosensor 300.

The sensor polarizing layer 225 may be formed at the lower part of the sensor retardation layer 210. The polarization axis of the sensor polarization layer 225 may be inclined at a second angle with respect to the slow axis of the sensor retardation layer 210. Further, the second light transmission layer 226 may be formed on the same plane as the sensor polarization layer 225. The second light transmitting layer 226 is laminated on the first light receiving portion 310 of the photosensor 300. The first light transmission layer 211 and the second light transmission layer 226 may be formed of materials with the same or similar light transmittance.

The above description of the present disclosure is exemplary. For those skilled in the art to which the present disclosure belongs, it can be understood that it can be easily transformed into other specific embodiments without changing the technical concept or essential features of the present disclosure. Way. Therefore, it should be understood that the above-described embodiments are all exemplary and not intended to be limiting. In addition, the features of the present disclosure described with reference to the drawings are not limited to the structures shown in the specific drawings, and can be implemented alone or in combination with other features.

The scope of the present disclosure is presented by the appended claims, rather than the above description. It should be understood that all changes or modifications are derived from the meaning and scope of the claims and their equivalent concepts All are included in the scope of the present disclosure.

Claims

An illuminance sensor in the lower part of the display is arranged on the lower part of the display including the pixels that generate light, the display retardation layer arranged on the upper part of the pixels, and the display polarizing layer, and measures the outside of the display Brightness, where

The illuminance sensor at the lower part of the display includes:

A light selection layer having a first light path and a second light path that travel by circularly polarized light of the display generated by external light incident from the outside of the display and unpolarized light generated by the pixels; and

The photosensor has a first light receiving unit that detects light passing through the first light path and a second light receiving unit that detects light passing through the second light path,

The first light path allows both the circularly polarized light of the display and the non-polarized light to pass,

The second light path blocks the circularly polarized light of the display and allows the non-polarized light to pass.
The illuminance sensor in the lower part of the display according to claim 1, wherein:

The light selection layer includes:

A sensor retardation layer for the circularly polarized light of the display to enter, and has an orthogonal slow axis and a fast axis;

The first sensor polarization layer is located at the lower part of the sensor delay layer and has a polarization axis inclined at a first angle with respect to the slow axis; and

The second sensor polarization layer is located at the lower part of the sensor delay layer and has a polarization axis inclined at a second angle with respect to the slow axis,

The sensor delay layer and the first sensor polarizing layer form the first light path,

The sensor delay layer and the second sensor polarizing layer form the second light path.
The illuminance sensor in the lower part of the display according to claim 2, wherein:

The plurality of first sensor polarizing layers and the plurality of second sensor polarizing layers are alternately arranged on the same plane.
The illuminance sensor in the lower part of the display according to claim 1, wherein:

The light selection layer includes:

The first sensor retardation layer, for the circularly polarized light to enter the display, and has a first slow axis and a first fast axis that are orthogonal;

The second sensor retardation layer, for the circularly polarized light of the display to enter, and has a second slow axis and a second fast axis that are orthogonal; and

The sensor polarization layer is located below the first sensor delay layer and the second sensor delay layer, and has a polarization axis inclined at a first angle with respect to the first slow axis,

The first slow axis is orthogonal to the second slow axis,

The first sensor retardation layer and the sensor polarizing layer form the first light path,

The second sensor delay layer and the sensor polarizing layer form the second light path.
The illuminance sensor in the lower part of the display according to claim 4, wherein:

The plurality of first sensor delay layers and the plurality of second sensor delay layers are alternately arranged on the same plane.
The illuminance sensor in the lower part of the display according to claim 1, wherein:

The light selection layer includes:

The first sensor retardation layer, for the circularly polarized light to enter the display, and has a first slow axis and a first fast axis that are orthogonal;

The second sensor retardation layer, for the circularly polarized light to enter the display, and has a second slow axis and a second fast axis orthogonal;

The first sensor polarization layer is located below the first sensor delay layer and the second sensor delay layer, and has a polarization axis inclined at a second angle with respect to the first slow axis; and

The second sensor polarization layer is located below the first sensor retardation layer and the second sensor retardation layer, and has a polarization axis inclined at a first angle with respect to the first slow axis,

The first slow axis is orthogonal to the second slow axis.
The illuminance sensor in the lower part of the display according to claim 6, wherein:

A plurality of said first sensor delay layers and a plurality of said second sensor delay layers are alternately arranged on a first plane,

The plurality of first sensor polarizing layers and the plurality of second sensor polarizing layers are alternately arranged on the second plane.
The illuminance sensor in the lower part of the display according to claim 2, 4 or 6, wherein:

The first light receiving unit detects linearly polarized light of the first sensor generated from the circularly polarized light of the display and linearly polarized light of the second sensor generated from the non-polarized light,

The second light receiving unit detects linearly polarized light of the third sensor generated from the non-polarized light.
The illuminance sensor in the lower part of the display according to claim 1, wherein:

The light selection layer includes:

A sensor retardation layer, for the circularly polarized light of the display to enter, and having an orthogonal slow axis and a fast axis; and

The sensor polarization layer is located at the lower part of the sensor delay layer and has a polarization axis inclined at a second angle with respect to the slow axis,

The sensor retardation layer and the sensor polarizing layer are arranged only on the upper part of the second light receiving part.
The illuminance sensor in the lower part of the display according to claim 1, wherein:

The illuminance sensor at the lower part of the display further includes a condenser lens formed on the upper surface of the light selection layer.
The illuminance sensor in the lower part of the display according to claim 1, wherein:

The brightness of the external light after passing through the first light path is corrected by applying a proportional relationship. The proportional relationship is that the first light path and the A proportional relationship is established between the brightness of the non-polarized light after the two light paths respectively pass.