CN112088292A

CN112088292A - Color illumination sensor at lower part of display

Info

Publication number: CN112088292A
Application number: CN202080001981.5A
Authority: CN
Inventors: 闵丙日
Original assignee: Hangzhou Xinge Microelectronics Co ltd
Current assignee: Hangzhou Xinge Microelectronics Co ltd
Priority date: 2020-04-26
Filing date: 2020-04-26
Publication date: 2020-12-15
Also published as: WO2021217308A1

Abstract

The invention relates to a color illumination sensor at the lower part of a display, which comprises: a light selection layer having a first optical path and a second optical path that are optical paths for allowing display circularly polarized light generated by outside light incident from the outside of the display and unpolarized light generated by the pixels to travel; a color filter layer disposed below the light selection layer, so that light passing through the first optical path and the second optical path passes through the color filter layer in different wavelength bands; and a photosensor disposed below the color filter layer, the photosensor including a first light receiving unit that detects light passing through the first optical path and a second light receiving unit that detects light passing through the second optical path, the first optical path allowing all of the display circularly polarized light and the unpolarized light to pass therethrough, the second optical path blocking the display circularly polarized light and allowing the unpolarized light to pass therethrough.

Description

Color illumination sensor at lower part of display

Technical Field

The present invention relates to a color illuminance sensor.

Background

The illuminance sensor is applied not only to portable electronic devices such as mobile phones and tablet computers but also to video electronic devices such as TVs and monitors. The illuminance sensor is a sensor that senses the brightness around the electronic device. Recently, designs in which displays occupy almost the entire front of electronic devices have been increasing. Although the size of the display becomes large in accordance with the demand for pursuing a large screen, it is still necessary to secure at least a partial area of the front surface in order to dispose the camera, particularly, in order to dispose the illuminance sensor. Although a proximity sensor using ultrasonic waves or the like can be applied to a structure in which the front surface is covered with a display, it is difficult to integrate an illuminance sensing function. The illuminance sensor may be disposed in a region other than the front surface, but may not be able to sense ambient light due to a housing that protects the electronic device. Therefore, although the most ideal position for installing the illuminance sensor is the front surface of the electronic device, it is difficult to ensure a position for arranging a commonly used illuminance sensor in a design in which the display occupies the entire front surface.

Disclosure of Invention

An object of the present invention is to provide a color illuminance sensor that can be applied to an electronic device designed so that a display occupies the entire front surface.

There is provided a color illuminance sensor at a lower portion of a display, the color illuminance sensor at the lower portion of the display being disposed at a lower portion of the display and measuring brightness around the display, the display including a pixel generating light, a display retardation layer disposed at an upper portion of the pixel, and a display polarizing layer. The color illumination sensor of the lower portion of the display may include: a light selection layer having a first optical path and a second optical path that are optical paths for allowing display circularly polarized light generated by outside light incident from the outside of the display and unpolarized light generated by the pixels to travel; a color filter layer disposed below the light selection layer, so that light passing through the first optical path and the second optical path passes through the color filter layer in different wavelength bands; and a photosensor disposed below the color filter layer, the photosensor including a first light receiving unit that detects light passing through the first optical path and a second light receiving unit that detects light passing through the second optical path, the first optical path allowing all of the display circularly polarized light and the unpolarized light to pass therethrough, the second optical path blocking the display circularly polarized light and allowing the unpolarized light to pass therethrough.

As an embodiment, the light selective layer may include: a sensor retardation layer for circularly polarized light incident on the display and having orthogonal slow and fast axes; a first sensor polarizing light layer located at a lower portion of the sensor retardation layer, having a polarizing optical axis inclined at a first angle with respect to the slow axis; and a second sensor polarizing layer located at a lower portion of the sensor retardation layer and having a polarizing axis inclined at a second angle with respect to the slow axis. Wherein the sensor retarder layer and the first sensor polarizing layer form the first optical path, and the sensor retarder layer and the second sensor polarizing layer are capable of forming the second optical path.

As an example, the plurality of first sensor polarizing layers and the plurality of second sensor polarizing layers may be alternately arranged on the same plane.

As an embodiment, the light selective layer may include: a first sensor retardation layer for circularly polarized light incident on the display and having orthogonal first slow and fast axes; a second sensor retardation layer for circularly polarized light incident on the display and having a second slow axis and a second fast axis orthogonal to each other; and a sensor polarizing light layer located at a lower portion of the first and second sensor retardation layers and having a polarization optical axis inclined at a first angle with respect to the first slow axis. Wherein the first slow axis and the second slow axis may be orthogonal, the first sensor retardation layer and the sensor polarizing layer may form the first optical path, and the second sensor retardation layer and the sensor polarizing layer may form the second optical path.

As an embodiment, a plurality of the first sensor delay layers and a plurality of the second sensor delay layers may be alternately arranged on the same plane.

As an embodiment, the light selective layer may include: a first sensor retardation layer for circularly polarized light incident on the display and having orthogonal first slow and fast axes; a second sensor retardation layer for circularly polarized light incident on the display and having a second slow axis and a second fast axis orthogonal to each other; a first sensor polarizing light layer located at a lower portion of the first sensor retardation layer and the second sensor retardation layer and having a polarizing optical axis inclined at a second angle with respect to the first slow axis; and a second sensor polarizing layer located at a lower portion of the first and second sensor retardation layers and having a polarization optical axis inclined at a first angle with respect to the first slow axis. Wherein the first slow axis and the second slow axis may be orthogonal.

For example, the plurality of first sensor retardation layers and the plurality of second sensor retardation layers may be alternately arranged on a first plane, and the plurality of first sensor polarizing layers and the plurality of second sensor polarizing layers may be alternately arranged on a second plane.

In one embodiment, the first light receiving unit may detect a first sensor linear polarized light generated from the display circular polarized light and a second sensor linear polarized light generated from the unpolarized light, and the second light receiving unit may detect a third sensor linear polarized light generated from the unpolarized light.

As an embodiment, the light selective layer may include: a sensor retardation layer for circularly polarized light incident on the display and having orthogonal slow and fast axes; a sensor polarizing light layer located at a lower portion of the sensor retardation layer and having a polarizing axis inclined at a second angle with respect to the slow axis. The sensor retardation layer and the sensor polarizing layer may be provided only on the upper portion of the second light receiving part.

As one embodiment, the color filter layer may be configured by a plurality of repeated filter units configured by 2N × N (where N and N are natural numbers equal to or greater than 1, and N is a kind of color filter) color filters, and the filter unit includes 2N same-kind color filters.

In the filter unit, the first light receiving unit may be disposed below n filters of the 2n filters of the same color, and the second light receiving unit may be disposed below the remaining n filters of the same color, respectively.

As an embodiment, in the filter unit, two filters of the same color may be disposed in contact with each other.

As an embodiment, in the filtering unit, two filters of the same color may be arranged at a distance.

As an example, the light sensor may measure the brightness of N different wavelength bands of light through N color filters.

In one embodiment, the plurality of first light receiving units and the plurality of second light receiving units each measure the luminance of light emitted from a sensor detection region defined in a lower surface of the display, and the plurality of measured values can be used to calculate an average luminance of light emitted from the sensor detection region.

The color illuminance sensor according to the embodiment of the present invention can be applied to an electronic device designed such that a display occupies the entire front surface.

Drawings

The invention will be described below with reference to an embodiment shown in the drawings. For the sake of understanding, the same constituent elements are denoted by the same reference numerals throughout the drawings. The structures shown in the drawings are illustrative of embodiments of the invention only and do not limit the scope of the invention. In particular, some components are shown in the drawings with some exaggeration to facilitate understanding of the invention. Since the drawings are for the purpose of understanding the invention, it is to be understood that the widths, thicknesses, and the like of the components shown in the drawings may be changed in practice.

Fig. 1 is a diagram for exemplarily explaining an operation principle of a color illuminance sensor at a lower portion of a display.

Fig. 2 is a diagram illustrating one embodiment of the light selection layer shown in fig. 1.

Fig. 3 is a diagram illustrating another embodiment of the light selection layer shown in fig. 1.

Fig. 4 is an exploded perspective view for illustrating one embodiment of a color illuminance sensor at a lower portion of a display.

Fig. 5 is an exploded perspective view for illustrating another embodiment of a color illuminance sensor at a lower portion of a display.

Fig. 6 is an exploded perspective view for illustrating still another embodiment of a color illuminance sensor at a lower portion of a display.

Fig. 7 is an exploded perspective view for illustrating still another embodiment of a color illuminance sensor at a lower portion of a display.

Fig. 8 and 9 are diagrams exemplarily illustrating filter units constituting a color filter layer.

Fig. 10 and 11 are diagrams exemplarily showing detection regions according to the arrangement of a plurality of same-color filters constituting a color filter pair.

Fig. 12 is a diagram for illustrating still another embodiment of the color illuminance sensor at the lower portion of the display.

Fig. 13 is an exploded perspective view for exemplarily explaining the color illuminance sensor at the lower portion of the display shown in fig. 12.

Detailed Description

While the invention is capable of various modifications and embodiments, specific embodiments thereof are shown in the drawings and will be described herein in detail. It should be understood that it is not intended to limit the present invention to the particular embodiments, but to include all modifications, equivalents, and alternatives falling within the spirit and scope of the present invention. In particular, functions, features, embodiments to be described below with reference to the drawings can be implemented alone or in combination with another embodiment. It should be noted, therefore, that the scope of the present invention is not limited by the illustrated embodiments.

On the other hand, with respect to terms used in the present specification, expressions such as "substantially", "almost", "about" and the like are expressions considering a difference (margin) allowed when substantially realized or an error may occur. For example, for "substantially 90 degrees", it should be construed that an angle capable of obtaining the same effect as that at 90 degrees is also included. As another example, "substantially free" should be construed to include to the extent that it is negligible, if at all.

On the other hand, "side" or "horizontal" means the left-right direction of the drawing, and "vertical" means the up-down direction of the drawing, unless otherwise mentioned. Unless otherwise specified, the angle, the incident angle, and the like are based on a virtual straight line perpendicular to the horizontal plane shown in the drawing.

The same reference numbers will be used throughout the drawings to refer to the same or like parts.

The sensor 100 at the lower portion of the display is disposed at the lower portion of the display 10. The display 10 includes: a pixel layer 13 in which a plurality of pixels P that generate light are formed; the display polarizing layer 11 and the display retardation layer 12 are stacked on 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 may be provided on the bottom surface of the display 10, the protective layer being formed of an opaque material, such as metal or synthetic resin. As an example, the sensor 100 under the display constituted by the light selective layer 200 and the light sensor 300 may be disposed in a region where a part of the protective layer is removed (hereinafter, referred to as a completed structure). As another example, the light selection layer 200 of the sensor 100 at the lower portion of the display may be manufactured in a film (film) form and laminated on the bottom surface of the display 10. The light sensor 300 is attached to the bottom surface of the light selection layer 200, thereby also realizing a color illumination sensor (hereinafter, referred to as an assembly structure) at the lower portion of the display. In the following, the description will be focused on the completed structure in order to avoid redundancy.

The display polarizing layer 11 and the display retarder layer 12 improve the visibility of the display 10. The extraneous 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 display linearly polarized light 21 substantially coincident with the polarization axis of the display polarizing layer 11 passes through the display polarizing layer 11. If the display linearly polarized light 21 passes through the display retardation layer 12, display circularly polarized light (or elliptically polarized light) 22 rotating in a clockwise or counterclockwise direction is formed. If the display circularly polarized light 22 is reflected by the pixel layer 13 to re-enter the display retarder layer 12, a second linearly polarized light is formed. 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 display linearly polarized light 21 and the polarization axis of the second linearly polarized light are orthogonal to each other. Therefore, the second linearly polarized light, i.e., 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. Therefore, the visibility of the display 10 can be improved.

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

The sensor 100 at the lower portion of the display includes: a light selective layer 200 having two light paths; and an optical sensor 300 for detecting light passing through each optical path. The light incident on the sensor 100 at the lower portion of the display is display circularly polarized light 22 generated by outside light and unpolarized light 30 generated inside the display. The first and second light paths within the light selective layer 200 contribute differently to the display circularly polarized light 22 and the unpolarized light 30. The first path passes all display circularly polarized light 22 and unpolarized light 30. Conversely, the second path passes unpolarized light 30 and substantially blocks display circularly polarized light 22. The display circularly polarized light 22 having passed through the first optical path becomes the first sensor linearly polarized light 23, and the unpolarized light 30 having passed through the first optical path and the second optical path becomes the second sensor linearly polarized light 31 and the third sensor linearly polarized light 32.

The optical sensor 300 includes a first light receiving part 311 corresponding to a first optical path and a second light receiving part 312 corresponding to a second optical path. For example, the first light receiving part 311 generates a first pixel current substantially proportional to the light amounts of the display circularly polarized light 22 and the unpolarized light 30, and the second light receiving part 312 generates a second pixel current substantially proportional to the light amount of the unpolarized light 30. The

light receiving unit

311 or 312 may be formed of, for example, one photodiode or a plurality of photodiodes (hereinafter, referred to as a PD array). As an example, one or two photodiodes may correspond to one pixel P. As another example, the PD array may correspond to one pixel P. As still another embodiment, one or two photodiodes may correspond to a plurality of pixels P. As still another embodiment, the PD array may correspond to a plurality of pixels P. Here, the first light receiving unit 311 and the second light receiving unit 312 can detect any one of light belonging to different wavelength bands such as red, green, blue, and white in common.

The color illuminance sensor is a device that measures the luminance of light in at least two or more wavelength bands in order to measure the luminance of outside light. When the color illuminance sensor is disposed below the display, not only the external light passing through the display but also the light generated inside the display enters the color illuminance sensor. Therefore, in order to accurately measure the luminance of light belonging to at least two or more wavelength bands at the same time, respectively, it is necessary to measure the luminance of light generated inside the display. If only the brightness of the light generated inside the display can be measured, it is possible with this to correct the measured brightness of the light of different wavelength bands.

As described above, the second sensor linear polarization 31 and the third sensor linear polarization 32 generated by the unpolarized light 30 can be detected by the first light receiving unit 311 and the second light receiving unit 312, respectively. In particular, since the sensor internal linearly polarized light generated from the display circularly polarized light 22 by the light selection layer 200 does not substantially enter the second light receiving part 312, the second light receiving part 312 can only measure the luminance of the third sensor linearly polarized light 32 generated from the unpolarized light 30. In addition, the brightness of the second sensor linear polarized light 31 and the third sensor linear polarized light 32 may be substantially the same, but may be different, which will be described in detail below. However, since the second sensor linear polarized light 31 and the third sensor linear polarized light 32 are generated from the non-polarized light 30 generated from one or a plurality of pixels, a linear proportional relationship or a non-linear proportional relationship is established between the luminance of the two. The nonlinear proportional relationship may be caused by various factors such as the structural characteristics of the display 10, the difference in pixel regions corresponding to the respective light receiving portions, and the wavelength band of the unpolarized light 30. The proportional relationship between the second sensor linear polarized light 31 and the third sensor linear polarized light 32 can be measured in an environment free from the influence of external light. According to the proportional relationship, the degree of contribution of the second sensor linearly polarized light 31 to the luminance measured by the first light receiving part 311 can be calculated from the luminance of the third sensor linearly polarized light 32 measured by the second light receiving part 312. Thus, the brightness of light of different wavelength bands can be precisely measured separately and simultaneously.

In all the drawings below, cross-sectional (Hatching) lines shown for the retardation layer indicate the direction of the slow axis, and cross-sectional lines shown for the polarizing layer exemplarily indicate the direction of the polarization optical axis with respect to the slow axis extending to the horizontal direction. In addition, the figures show that the slow axis of the display retarder and the slow axis of the sensor retarder both extend in the horizontal direction, or the slow axis of the display retarder and the slow axis of the sensor retarder both extend in the vertical direction. It should be understood that this is a simple expression for ease of understanding and does not require the slow axis of the sensor retarder to be aligned with the slow axis of the display retarder. In order to simplify the drawing, only light emitted through the light selection layer is shown for unpolarized light emitted from the pixel P.

The light selection layer 200 includes a sensor retardation layer 120, a first sensor polarizing light layer 110, and a second sensor polarizing light layer 115. The sensor retardation layer 120 is disposed on the first sensor polarizing layer 110 and the second sensor polarizing layer 115, and the optical sensor 300 is disposed under the first sensor polarizing layer 110 and the second sensor polarizing layer 115. A color filter layer 320 is disposed between the first sensor polarizing layer 110 and the second sensor polarizing layer 115, and the optical sensor 300, and the color filter layer 320 limits the wavelength band of light incident on the light receiving part 310. The light receiving unit 310 of the optical sensor 300 includes a first light receiving unit 311 and a second light receiving unit 312. The first light receiving part 311 is disposed below the first sensor polarizing layer 110, and the second light receiving part 312 is disposed below the second sensor polarizing layer 115. For one embodiment, the light selective layer 200 may be fabricated by laminating (laminating) the sensor retardation layer 120 on the upper surfaces of the first sensor polarizing light layer 110 and the second sensor polarizing light layer 115. The light selective 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 selective layer 200. As another example, the light sensor 300 may be implemented by a thin film transistor. Therefore, the color illuminance sensor 100 under the display can be manufactured by laminating the film-shaped sensor retardation layer 120, the first and second

sensor polarizing layers

110 and 115, and the optical sensor 300.

The polarization axis of the first sensor polarizing light layer 110 and the polarization axis of the second sensor polarizing light layer 115 are tilted at different angles with respect to the slow axis of the sensor retardation layer 120. The polarization axis of the first sensor polarizing light layer 110 is tilted at a first angle, e.g., +45 degrees, with respect to the slow axis of the sensor retardation layer 120, and the polarization axis of the second sensor polarizing light layer 115 is tilted at a second angle, e.g., -45 degrees, with respect to the slow axis of the sensor retardation layer 120.

The first light receiving part 311 of the optical sensor 300 detects the first sensor linearly polarized light 23 and the second sensor linearly polarized light 31 emitted from the first sensor polarizing layer 110, and the second light receiving part 312 detects the third sensor linearly polarized light 32 emitted from the second sensor polarizing layer 115. The light receiving unit 310 can generate a pixel current having a magnitude corresponding to the light amount of light in each wavelength band. The light receiving unit 310 may be, for example, a photodiode, but is not limited thereto.

The color filter layer 320 is located between the light sensor 300 and the light selection layer 200. Specifically, the color filter layer 320 may be formed of, for example, red (R), green (G), blue (B), and white (W) filters. Each color filter may be substantially vertically above the first light receiving part 311 or the second light receiving part 312. The color filter passes light belonging to a specific wavelength band and blocks light not belonging to the specific wavelength band. The color filter layer 320 is described in detail with reference to fig. 4 to 11.

Next, the operation of the color illuminance sensor 100 under the display having the light selection layer 200 having the above-described structure will be described.

Display circularly polarized light 22 and unpolarized light (30 in fig. 1, not shown in fig. 4 to 11) are incident on the upper surface of the light selection layer 200, i.e. the upper surface of the sensor retardation layer 120. The display circularly polarized light 22 is light in which the external light 20 passes through the display polarizing layer 11 and the display retardation layer 12, and the unpolarized light 30 travels downward from the pixel P toward the light selection layer 200.

The display polarizing layer 11 may have a polarizing axis that is tilted at a second angle, e.g., -45 degrees, with respect to the slow axis of the display retarder layer 12. Thus, display linearly polarized light 21 after passing through the display polarizing layer 11 may be incident at a second angle relative to the slow axis of the display retarder layer 12. If the first polarized light portion of the display linearly polarized light 21 transmitted along the fast axis and the second polarized light portion of the display linearly polarized light 21 transmitted along the slow axis pass through the display retarder layer 12, a phase difference of λ/4 is generated therebetween. Therefore, the display linearly polarized light 21 after passing through the display retardation layer 12 can become display circularly polarized light 22 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 sensor internal linearly polarized light 22a by the sensor retardation layer 120. The polarization axis of the sensor internal linearly polarized light 22a and the polarization axis of the display linearly polarized light 21 are orthogonal to each other. Unpolarized light 30, on the other hand, passes directly through the sensor retardation layer 120.

The polarization axis of the first sensor polarization light layer 110 and the polarization axis of the sensor internal linearly polarized light 22a are substantially parallel, so that the sensor internal linearly polarized light 22a emitted from the sensor retardation layer 120 can pass through the first sensor polarization light layer 110. On the contrary, the polarization axis of the second sensor polarization layer 115 is substantially perpendicular to the polarization axis of the sensor internal linearly polarized light 22a, so the sensor internal linearly polarized light 22a can be blocked by the second sensor polarization layer 115. The unpolarized light 30 emitted from the sensor retardation layer 120 passes through the first sensor polarizing layer 110 and the second sensor polarizing layer 115, and becomes the second sensor linearly polarized light 31 and the third sensor linearly polarized light 32, respectively. The first sensor linear polarized light 23, the second sensor linear polarized light 31, and the third sensor linear polarized light 32 pass through the same type of color filter (hereinafter, referred to as the same type of color filter), and then enter the optical sensor 300. In other words, the first light receiving unit 311 can detect the first sensor linearly polarized light 23 and the second sensor linearly polarized light 31 through the first optical path formed by the sensor retardation layer 120 and the first sensor polarizing layer 110, and the second light receiving unit 312 can detect the third sensor linearly polarized light 32 through the second optical path formed by the sensor retardation layer 120 and the second sensor polarizing layer 115.

The light selective layer 201 includes a first sensor retardation layer 120, a second sensor retardation layer 125, and a sensor polarizing light layer 110. The first sensor retardation layer 120 and the second sensor retardation layer 125 are disposed on the sensor polarizing layer 110, and the optical sensor 300 is disposed under the sensor polarizing layer 110. A color filter layer 320 is disposed between the sensor polarizing layer 110 and the light sensor 300, and the color filter layer 320 limits the wavelength band of light incident on the light receiving part 310. The first light receiving part 311 of the optical sensor 300 is disposed at a position where light emitted from the first sensor retardation layer 120 reaches after passing through the sensor polarizing layer 110, and the second light receiving part 312 is disposed at a position where light emitted from the second sensor retardation layer 125 reaches after passing through the sensor polarizing layer 110. For one embodiment, the light selective layer 201 may be fabricated by laminating a first sensor retardation layer 120 and a second sensor retardation layer 125 on the upper surface of the sensor polarizing light layer 110. The light selective 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 selective layer 201. As another example, the light sensor 300 may be implemented by a thin film transistor. Therefore, the color illuminance sensor 100 under the display can be manufactured by laminating the film-shaped first and second sensor retardation layers 120 and 125, the sensor polarizing layer 110, and the optical sensor 300.

The slow axis of the first sensor delay layer 120 and the slow axis of the second sensor delay layer 125 are substantially orthogonal. The polarization optical axis of the sensor polarizing light layer 110 may be tilted at a first angle, e.g., +45 degrees, with respect to the slow axis of the first sensor retardation layer 120, or at a second angle, e.g., -45 degrees, with respect to the slow axis of the second sensor retardation layer 125.

The first light receiving unit 311 of the optical sensor 300 is located vertically below the first sensor retardation layer 120, and detects the first sensor linearly polarized light 23 and the second sensor linearly polarized light 31, which are light emitted from the display circularly polarized light 22 through the first sensor retardation layer 120 and the sensor polarizing layer 110. The second light receiving part 312 of the photosensor 300 is located vertically below the second sensor retardation layer 125, thereby detecting the third sensor linearly polarized light 32. The

light receiving portions

311 and 312 can generate pixel currents having magnitudes corresponding to the light amounts of the detected light. The light receiving unit 310 can generate a pixel current having a magnitude corresponding to the light amount of light in different wavelength bands. The light receiving unit 310 may be, for example, a photodiode, but is not limited thereto.

Next, the operation of the color illuminance sensor 100 under the display having the light selection layer 201 having the above-described structure will be described. The display circularly polarized light 22 and the unpolarized light 30 are explained in the same manner as in fig. 2, and therefore, the explanation thereof is omitted.

Display circularly polarized light 22 and unpolarized light (30 in fig. 1, not shown in fig. 4 to 11) are incident on the upper surface of the light selective layer 201, i.e., the upper surfaces of the first sensor retardation layer 120 and the second sensor retardation layer 125. 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 internally linearly polarized light 22b by the first sensor retardation layer 120, and becomes the second sensor internally linearly polarized light 22c by the second sensor retardation layer 125. The slow axis of the first sensor retardation layer 120 and the slow axis of the second sensor retardation layer 125 are orthogonal, and therefore the polarization axis of the first sensor inner linearly polarized light 22b and the polarization axis of the second sensor inner linearly polarized light 22c can also be orthogonal. Specifically, the display circularly polarized light 22 having the phase difference of λ/4 between the first polarized light portion and the second polarized light portion can be converted into the first sensor internally linearly polarized light 22b having the polarization axis substantially parallel to the polarization axis of the display linearly polarized light 21 by eliminating the phase difference by the first sensor retardation layer 120. On the contrary, the display circularly polarized light 22 increases the phase difference of λ/4 by the second sensor retardation layer 125, and can become the second sensor internally linearly polarized light 22c having the polarization axis perpendicular to the polarization axis of the display polarized light 21. On the other hand, unpolarized light 30 passes directly through the first and second sensor retardation layers 120, 125.

Although the first sensor internal linearly polarized light 22b emitted from the first sensor retardation layer 120 passes through the sensor polarizing layer 110, the second sensor internal linearly polarized light 22c emitted from the second sensor retardation layer 125 cannot pass through the sensor polarizing layer 110. The sensor polarizing light layer 110 may have a polarization axis that is tilted at a first angle, e.g., -45 degrees, with respect to the slow axis of the first sensor retardation layer 120, or a polarization axis that is tilted at a second angle, e.g., +45 degrees, with respect to the slow axis of the second sensor retardation layer 125. Thus, the polarization axis of the first sensor internal linearly polarized light 22b is substantially parallel to the polarization axis of the sensor polarizing layer 110, and therefore the first sensor internal linearly polarized light 22b can pass through the sensor polarizing layer 110 almost without loss. On the contrary, the polarization axis of the second sensor internal linearly polarized light 22c is substantially perpendicular to the polarization axis of the sensor polarization layer 110, so that the second sensor internal linearly polarized light 22c can be blocked by the sensor polarization layer 110. The unpolarized light 30 having passed through the first and second sensor retardation layers 120 and 125 passes through the sensor polarizing layer 110 to become the second sensor linearly polarized light 31 and the third sensor linearly polarized light 32. The first sensor linear polarized light 23, the second sensor linear polarized light 31 and the third sensor linear polarized light 32 pass through the same color filter and enter the optical sensor 300. In other words, the first light receiving unit 311 can detect the first sensor linearly polarized light 23 and the second sensor linearly polarized light 31 through the first optical path formed by the first sensor retardation layer 120 and the sensor polarizing layer 110. On the other hand, the second light receiving unit 312 can detect the third sensor linear polarization 32 through the second optical path formed by the second sensor retardation layer 125 and the sensor polarization layer 110.

Fig. 4 is an exploded perspective view for illustrating one embodiment of a color illumination sensor at a lower portion of a display, relating to a structure to which the light selection layer shown in fig. 2 is applied.

As described above, the color illuminance sensor 400 at the lower portion of the display may be manufactured by laminating the sensor retardation layer 410, the sensor polarizing layer 420, the color filter layer 430, and the light sensor 440. Here, at least the sensor retardation layer 410 and the sensor polarizing light layer 420 may be film-shaped.

The sensor delay layer 410 may be the first sensor delay layer 120 having a slow axis formed in a substantially horizontal manner as a whole.

The sensor polarizing layer 420 is disposed at a lower portion of the sensor retardation layer 410. The sensor polarizing layer 420 may be formed by alternately arranging the first sensor polarizing layer 110 and the second sensor polarizing layer 115 having different polarizing axes along the first direction. The first sensor polarizing light layer 110 and the second sensor polarizing light layer 115 may have a rectangular shape extending along the second direction. Here, the polarization optical axis of the first sensor polarizing light layer 110 may be inclined at a first angle with respect to the slow axis of the sensor retardation layer 410, and the polarization optical axis of the second sensor polarizing light layer 115 may be inclined at a second angle with respect to the slow axis of the sensor retardation layer 410.

The color filter layer 430 is disposed under the sensor polarizing layer 420. The color filter layer 430 is capable of passing light belonging to a specific wavelength band and blocking light belonging to the remaining wavelength bands. The color filter layer 430 may include, for example: red filter CF for passing only light in red wavelength band_RAnd a green filter CF for passing only light in a green wavelength band_GAnd a blue filter CF for passing only light in the blue wavelength band_BAnd a white filter CF for passing only light in a white wavelength band_W. The color filters included in the color filter layer 430 may be disposed vertically above the light-receiving portions of the photosensor 440 so as to correspond to the light-receiving portions. In the drawing, the color filter layer 430 is illustrated in a separate film shape like the sensor retardation layer 410 and the sensor polarizing light layer 420, but this is merely an example. In other words, the color filter may be formed in advance in the light sensor 440.

The color filter layer 430 is configured by a plurality of repeated filter units (Unit patterns). In the filtering unit, the number of the same color filters is a multiple of 2, namely 2N (wherein N is more than or equal to 1), and N different color filters are arranged in the filtering unit. The 2n same-type color filters are arranged in contact with each other, that is, arranged such that there is no other type of color filter (hereinafter, referred to as a different-type color filter) between the two same-type color filters, or arranged at a distance (that is, there are a certain number of different-type color filters between the two same-type color filters).

The light having a relatively large amount of light and the light having a relatively small amount of light pass through the color filter layer 430 due to the sensor retardation layer 410 and the sensor polarizing light layer 420. Here, the light having a relatively large light amount may be the first sensor linearly polarized light 23 and the second sensor linearly polarized light 31, the light having a relatively small light amount may be the third sensor linearly polarized light 32, and "relative" refers to a comparison therebetween. Of the 2n same-color filters included in the filter unit, n color filters pass only light of a specific wavelength band included in light having a relatively large light quantity, and the remaining n color filters pass only light of a specific wavelength band included in light having a relatively small light quantity. For example, among the first and second red filters included in the filter unit, the first red filter allows only light in a red wavelength band included in light having a relatively large amount of light to pass therethrough, and the second color filter allows only light in a red wavelength band included in light having a relatively small amount of light to pass therethrough.

The photo sensor 440 is disposed below the color filter layer 430. The optical sensor 440 includes at least one pair of light receiving

portions

311 and 312 that detect light belonging to the same wavelength band. At least one pair of light receiving

portions

311, 312 correspond to at least one pair of same color filters included in the color filter layer 430, respectively. The plurality of light receiving

portions

311 and 312 output pixel currents having magnitudes corresponding to the light amounts of the light incident through the color filters. The wavelength bands of light detected by the first light receiving part 311 and the second light receiving part 312 are determined according to the types of color filters located substantially vertically above. The pair of light receiving

sections

311 and 312 are substantially the same light receiving section, and the first light receiving section 311 at a position where light having a relatively large amount of light belonging to the same wavelength band is incident is denoted by a subscript "B", and the second light receiving section 312 at a position where light having a relatively small amount of light belonging to the same wavelength band is incident is denoted by a subscript "D".

Since the first sensor polarization layer 110 of the sensor polarization layer 420 allows the first sensor linearly polarized light 23 and the second sensor linearly polarized light 31 to pass therethrough (i.e., the first optical path), the light receiving part disposed below the first sensor polarization layer 110 along the longitudinal direction of the first sensor polarization layer 110, that is, the second direction is the first light receiving part 311. On the other hand, since the second sensor layer 115 allows only the third sensor linear polarization 32 to pass therethrough (i.e., the second optical path), the light receiving part disposed below the second sensor polarization layer 115 along the longitudinal direction of the second sensor polarization layer 115, that is, the second direction is the second light receiving part 312.

Fig. 5 is an exploded perspective view for illustrating another embodiment of a color illuminance sensor at a lower portion of a display, relating to a structure to which the light selection layer shown in fig. 3 is applied. The description of the same parts as those in fig. 4 is omitted, and only the differences will be described.

The color illuminance sensor 401 at the lower portion of the display may include a sensor retardation layer 411, a sensor polarizing layer 421, a color filter layer 430, and a light sensor 440.

The sensor retardation layer 411 may be formed by alternately arranging a first sensor retardation layer 120 having a first slow axis and a second sensor retardation layer 125 having a second slow axis in a first direction. Here, the first slow axis and the second slow axis may be substantially orthogonal. The first sensor delay layer 120 and the second sensor delay layer 125 may have a rectangular shape extending in the second direction. Here, the first slow axis may be inclined at a first angle with respect to the polarization optical axis of the sensor polarizing light layer 421, and the second slow axis may be inclined at a second angle with respect to the polarization optical axis of the sensor polarizing light layer 421.

The sensor polarizing layer 421 is disposed below the sensor retardation layer 411. The sensor polarizing-light layer 421 may be the first sensor polarizing-light layer 110 formed with a polarizing axis in the same manner as a whole.

The color filter layer 430 is disposed under the sensor polarizing layer 421, and the color filter layer 430 is composed of a plurality of repeated filter units. The photo sensor 440 is disposed below the color filter layer 430. The optical sensor 440 includes at least one pair of light receiving

portions

311 and 312 that detect light belonging to the same wavelength band.

The sensor polarization layer 421 allows the first sensor internal linearly polarized light 22b and the second sensor linearly polarized light 31 passing through the first sensor retardation layer 120 to pass therethrough, and thus a light receiving part disposed below the sensor polarization layer 111 along the longitudinal direction of the first sensor retardation layer 120, that is, the second direction is the first light receiving part 311. On the other hand, since the second sensor polarization layer 115 allows only the third sensor linear polarization 32 passing through the second sensor retardation layer 125 to pass therethrough, the light receiving part disposed below the sensor polarization layer 111 along the longitudinal direction of the second sensor retardation layer 125, that is, the second direction is the second light receiving part 312.

Fig. 6 is an exploded perspective view for illustrating still another embodiment of a color illuminance sensor at a lower portion of a display. The same portions as those in fig. 4 and 5 will not be described, and only the differences will be described.

The color illumination sensor 402 at the lower portion of the display may include a sensor retardation layer 410, a sensor polarizing layer 422, a color filter layer 432, and a light sensor 442.

The sensor polarizing light layer 422 may be formed by alternately arranging the first sensor polarizing light layer 110 and the second sensor polarizing light layer 115 having different polarization axes. The first sensor polarizing light layer 110 and the second sensor polarizing light layer 115 may have a rectangular shape. Thus, the sensor polarizing layer 420 may have a structure in which each side of the first sensor polarizing layer 110 is in contact with four second sensor polarizing layers 115, or have each side of the second sensor polarizing layers 115 in contact with four first sensor polarizing layers 110. Here, the polarization optical axis of the first sensor polarizing light layer 110 may be inclined at a first angle with respect to the slow axis of the sensor retardation layer 410, and the polarization optical axis of the second sensor polarizing light layer 115 may be inclined at a second angle with respect to the slow axis of the sensor retardation layer 410.

The color filter layer 432 is disposed below the sensor polarizing layer 422, and the color filter layer 432 is formed of a plurality of filter units that overlap. The photo sensor 442 is disposed below the color filter layer 432. The photosensor 442 includes at least one pair of light receiving

portions

311 and 312 that detect light belonging to the same wavelength band.

The first sensor polarization layer 110 of the sensor polarization layer 422 allows the first sensor linearly polarized light 23 and the second sensor linearly polarized light 31 to pass therethrough, and thus the light receiving part disposed below the first sensor polarization layer 110 is the first light receiving part 311. On the other hand, since the second sensor polarization layer 115 allows only the third sensor linear polarization 32 to pass therethrough, the light receiving part disposed below the second sensor polarization layer 115 is the second light receiving part 312. Accordingly, the planar arrangement structure of the first light receiving part 311 and the second light receiving part 312 can be substantially the same as the sensor polarizing layer 420.

Fig. 7 is an exploded perspective view for illustrating still another embodiment of a color illuminance sensor at a lower portion of a display. Descriptions of the same parts as those in fig. 4 to 6 are omitted, and only differences will be described.

The color illuminance sensor 403 at the lower part of the display may include a sensor retardation layer 411, a sensor polarizing layer 423, a color filter layer 432, and a light sensor 442.

The sensor retardation layer 411 may be formed by alternately arranging a first sensor retardation layer 120 having a first slow axis and a second sensor retardation layer 125 having a second slow axis in a first direction. The first sensor delay layer 120 and the second sensor delay layer 125 may have a rectangular shape extending in the second direction. Here, the first slow axis and the second slow axis may be substantially orthogonal.

The sensor polarizing layer 423 may be formed by alternately arranging the first sensor polarizing layer 110 having the first polarization axis and the second sensor polarizing layer 115 having the second polarization axis in the second direction. The first sensor polarizing light layer 110 and the second sensor polarizing light layer 115 may have a rectangular shape extending in a first direction. Here, the polarization optical axis of the first sensor polarizing light layer 110 may be tilted at a first angle with respect to the slow axis of the first sensor retardation layer 120, and the polarization optical axis of the second sensor polarizing light layer 115 may be tilted at a second angle with respect to the slow axis of the first sensor retardation layer 120.

The color filter layer 432 is disposed below the sensor polarizing layer 423, and the color filter layer 432 is formed of a plurality of overlapping filter units. The photo sensor 442 is disposed below the color filter layer 432. The photosensor 442 includes at least one pair of light receiving

portions

311 and 312 that detect light belonging to the same wavelength band.

The first sensor retardation layer 120-the second sensor polarizing layer 115-and the second sensor retardation layer 125-the first sensor polarizing layer 110 are first optical paths through which the first sensor linearly polarized light 23 and the second sensor linearly polarized light 31 pass. The first sensor retarder 120-first sensor polarizing light layer 110 and the second sensor retarder 125-second sensor polarizing light layer 115 are second optical paths that only allow third sensor linearly polarized light 32 to pass through. Thus, the planar arrangement structure of the first light receiving parts 311 and the second light receiving parts 312 may have a structure in which each side of the first light receiving part 311 is in contact with four second light receiving parts 312, or a structure in which each side of the second light receiving part 312 is in contact with four first light receiving parts 311.

The types of the color filter layers are N (wherein N is more than or equal to 1), and the total number of the color filters contained in the filter unit is 2N multiplied by N, which is the minimum value. As described above, in the filter unit, the number of filters of the same color is 2n (where n.gtoreq.1). The filtering unit may be repeated in the first direction, the second direction, and a combination thereof. As an example, fig. 8 shows a filter unit in which four color filters are respectively 4 and arranged at 4 × 4, and fig. 9 shows a filter unit in which four color filters are respectively 2 and arranged at 2 × 4, and in order to facilitate understanding, the color filters at positions where light having a relatively large amount of light belonging to the same wavelength band is incident are denoted by a subscript "B", and the color filters at positions where light having a relatively small amount of light belonging to the same wavelength band is incident are denoted by a subscript "D", in the same manner as the optical sensors of fig. 4 to 7.

Fig. 8 (a) shows a filter unit in which the first color filter pair and the second color filter pair are arranged in a separated manner. The color filter pair is composed of two (or more) color filters of the same kind. Light having a relatively large amount of light passes through any one of the color filters (color filter denoted by subscript "B") constituting the color filter pair and reaches the first light-receiving part, and light having a relatively small amount of light passes through the remaining color filters (color filter denoted by subscript "D") and reaches the second light-receiving part. Two color filters in each color filter pair are arranged in contact with each other, and a color filter pair composed of different color filters is arranged around a color filter pair composed of one color filter.

On the other hand, in the filter unit, the first color filter pair 500 and the second color filter pair 510 are not located in the same column. Taking a red filter as an example, the first red filter pair 500 is composed of two red filters in columns c1 and c2 of row r1, and the second red filter pair 510 is composed of two red filters in columns c3 and c4 of row r 3.

Fig. 8 (b) shows a filter unit in which a first color filter pair and a second color filter pair each including two filters of the same color are arranged in a separated manner. In each color filter pair, two color filters are arranged separately. In other words, more than one different color filter may be disposed between two same-type color filters. Therefore, different color filters are arranged around one color filter.

On the other hand, in the filter unit, the first color filter pair 520 and the second color filter pair 530 are not located in the same column. Taking a red filter as an example, the first red filter pair 520 is composed of two red filters in columns c1 and c3 of row r1, and the second red filter pair 530 is composed of two red filters in columns c2 and c4 of row r 3.

Fig. 9 (a) shows a filter unit configured with four color filter pairs. Each color filter pair is composed of two filters of the same color. In each color filter pair, two color filters are arranged in contact with each other. The light having a relatively large amount of light passes through one of the two color filters (color filter denoted by the lower corner "B") disposed in contact, and the light having a relatively small amount of light passes through the remaining color filter (color filter denoted by the lower corner "D"). A color filter pair composed of different color filters is arranged around a color filter pair composed of one color filter. In the filter unit shown in fig. 9 (a), a red filter pair is disposed in columns c1 and c2 of row r1, a green filter pair is disposed in columns c3 and c4 of row r1, a blue filter pair is disposed in columns c1 and c2 of row r2, and a white filter pair is disposed in columns c3 and c4 of row r 2.

Fig. 9 (b) shows a filter unit in which four color filter pairs are arranged. Each color filter pair is composed of two filters of the same color. In each color filter pair, two color filters are arranged separately. In other words, more than one different color filter may be disposed between two same color filters. Therefore, different color filters are arranged around one color filter. In the filter unit shown in fig. 9 (b), a red filter pair is disposed in columns c1 and c3 of row r1, a green filter pair is disposed in columns c2 and c4 of row r1, a blue filter pair is disposed in columns c1 and c3 of row r2, and a white filter pair is disposed in columns c2 and c4 of row r 2.

Fig. 10 and 11 are diagrams exemplarily showing detection regions according to the arrangement of a plurality of same-color filters constituting a color filter pair, fig. 10 showing a case where a color filter layer having a filter unit shown in (a) of fig. 8 is applied, and fig. 11 showing a case where a color filter layer having a filter unit shown in (b) of fig. 8 is applied. Reference numeral 300R_BThe first light receiving part R emphasizes the detection of light belonging to a red wavelength band with a relatively large light quantity_B300R, reference numeral 300R_DThe second light receiving part R emphasizes the detection of light belonging to a red wavelength band with a relatively large light quantity_BThe optical sensor of (1).

Reference numerals

10a, 10b, and 10c denote sensor detection regions defined in a lower portion of the display 10, in other words, regions in which the light sensor can sense light emitted from the display 10. The sensor detection region 10a is marked with a first light receiving part R_BA plurality of sub-regions 10rb capable of detecting light, and a second light receiving part R is marked on the sensor detection region 10b_DA plurality of sub-areas 10rd capable of detecting light. Both the plurality of sub-areas 10rb and the plurality of sub-areas 10rd are marked on the sensor detection area 10 c.

Compared with a measurement mode of not distinguishing the light wave band, the measurement mode of distinguishing the light wave band can relatively more accurately measure the surrounding brightness, namely, the illumination. In particular, if light belonging to the same wavelength band is caused to pass through the light selective layer so as to be separated into light having a relatively large amount of light and light having a relatively small amount of light, the ambient brightness of the electronic device can be accurately measured even in the lower portion of the display. In addition, the color temperature can be calculated from the brightness of light of different wavelength bands. The calculated color temperature is provided to a display or a camera of the electronic device, and thus can be used to correct an image displayed on the display or an image captured by the camera.

Referring to fig. 10, the color filter pair is composed of two filters of the same color, which are disposed in contact with each other. If two filter units with the same color filter in contact configuration are applied to the photosensor, the first light receiving part R_BAnd a second light receiving part R_DAt least a portion of the separately detected light may exit from the overlapping sub-regions. The closer the two filters of the same color are, the first light receiver R is emitted_BAnd a second light receiving part R_DThe more the area of the overlapping area Overlap on the lower surface of the display for the co-detected light increases. In addition, if the first light receiving part R_BAnd a second light receiving part R_DOr the first light receiving part R_BAnd a second light receiving part R_DThe distance from the lower surface of the display increases, and the area of the overlapping area Overlap increases. First light receiving part R_BAnd a second light receiving part R_DBy detecting light of a relatively large amount and light of a relatively small amount, which are generated by light emitted from the overlapping region Overlap, at a plurality of positions within the sensor detection region 10c, ambient brightness measurement can be performed.

On the other hand, referring to fig. 11, the color filter pair is composed of two filters of the same color, and the two filters of the same color are arranged separately. If two filter units with the same color filter arranged separately are applied to the light sensor, the first light receiving part R is emitted_BAnd a first light receiving part R_DThe area of the overlapping region of the commonly detected lights may be relatively reduced compared to that shown in fig. 10. Conversely, the first light receiving part R_BAnd a first light receiving part R_DThe area of the sensor detection region 10c capable of detecting light can be relatively increased as compared with that shown in fig. 10. As shown in fig. 11, the plurality of first light receiving parts R included in the optical sensor 300_BAnd a first light receiving part R_DLight emitted from substantially the entire area of the sensor detection region 10c can be sensed. In other wordsIn other words, the plurality of first light receiving parts R_BAnd a second light receiving part R_DIt is possible to detect light of a relatively large amount of light and light of a relatively small amount of light generated by light emitted from substantially the entire area of the sensor detection region 10 c. Thereby, the ambient brightness can be measured over the entire sensor detection region 10 c. For example, the plurality of first light receiving parts R_BAll of the generated measured values of the light having a relatively large light amount are used to calculate the average brightness of the light having a relatively large light amount emitted from the sensor detection region, and similarly, the plurality of second light receiving portions R_DThe generated measured values of light having a relatively small amount of light are all used to calculate the average luminance of light having a relatively small amount of light emitted from the sensor detection area. It is needless to say that the calculation of the average value for the sensor detection region can be applied to the case shown in fig. 10.

The pixel impact of the display can be reduced considerably by using the average brightness of the regions. The pixels of the display are turned on or off, for example, according to the displayed image, and the intensity of the emitted light is also different. Therefore, when the light receiving unit of the photosensor detects light emitted from a specific pixel or several to several tens of pixels, the ambient brightness calculated from the measured value may be severely distorted (deviated from the actual value). Even if the average luminance of the entire sensor detection region is used, the light generated by the specific pixel affects a part of the light receiving section, and the measured value may be locally distorted. However, even if part of the measured values are distorted, the influence on the average luminance is insignificant.

Fig. 12 is a diagram for illustrating still another embodiment of the color illuminance sensor at the lower portion of the display. The description overlapping with fig. 1 is omitted, and the differences will be emphasized.

The color illuminance sensor 404 at the lower part of the display is disposed at the lower part of the display 10. The color illumination sensor 404 at the lower part of the display includes: a light selective layer 202 having two light paths; a color filter layer 330 disposed below the light selective layer 202; and an optical sensor 300 disposed below the color filter layer 330 and detecting light passing through each optical path. The light incident on the color illuminance sensor 404 in the lower part of the display is display circularly polarized light 22 generated from outside light 20 and unpolarized light 30 generated inside the display.

The first and second light paths within the light selective layer 202 contribute differently to the display circularly polarized light 22 and the unpolarized light 30. The first optical path allows the display circularly polarized light 22 and the unpolarized light 30 to pass directly. The display circularly polarized light 22 and the unpolarized light 30 having passed through the first optical path reach the first light receiving unit 311. Conversely, the second optical path passes unpolarized light 30 and substantially blocks display circularly polarized light 22. The unpolarized light 30 having passed through the second optical path becomes the third sensor linearly polarized light 32 and reaches the second light receiving unit 312.

The display circularly polarized light 22 and the unpolarized light 30 can be detected by the first light receiving unit 311, and the third sensor linearly polarized light 32 can be detected by the second light receiving unit 312. Since the linearly polarized light generated from the display circularly polarized light 22 by the light selection layer 202 cannot enter the second light receiving part 312, the second light receiving part 312 can measure only the luminance of the third sensor linearly polarized light 32 generated from the unpolarized light 30. A first proportional relationship is established between the luminance of the display circularly polarized light 22 and the luminance of the extraneous light 22, and a second proportional relationship is established between the unpolarized light 30 and the third sensor linearly polarized light 32. Here, the first proportional relationship and the second proportional relationship may be linear or non-linear, the first proportional relationship may be determined according to a result measured in a state where all pixels of the display 10 are turned off, and the second proportional relationship may be determined according to a result measured in a state where the pixels of the display 10 are turned off in a state where the extraneous light 22 is not present. After the brightness detected by the first light receiving unit 311 is corrected by the second proportional relationship, the brightness of the external light 20 can be specified by applying the first proportional relationship to the corrected brightness.

As described above, the color illuminance sensor 600 at the lower portion of the display may be manufactured by laminating the sensor retardation layer 610, the sensor polarizing layer 620, the color filter layer 630, and the light sensor 640. Here, at least the sensor retardation layer 610 and the sensor polarizing light layer 620 may be film-shaped.

The sensor retardation layer 610 may be formed by alternately arranging the first sensor retardation layer 120 having the first slow axis and the first light transmissive layer 127 that transmits incident light in the first direction. The first sensor retardation layer 120 and the first light transmission layer 127 may have a rectangular shape extending along the second direction. Here, the first slow axis may be inclined at a second angle with respect to a second polarization optical axis of the sensor polarizing layer 620.

The sensor polarizing layer 620 is disposed at a lower portion of the sensor retardation layer 610. The sensor polarizing layer 620 may be formed by alternately arranging the second sensor polarizing layer 115 having the second polarization axis and the second light transmissive layer 117 that transmits incident light in the first direction. The second sensor polarizing layer 115 and the second light transmissive layer 117 may have a rectangular shape extending along the second direction. First light transmission layer 127 and second light transmission layer 117 may be formed of substances having the same or similar light transmission rates.

The color filter layer 630 is disposed under the sensor polarizing layer 620, and the color filter layer 630 is composed of a plurality of repeated filter units. The photo sensor 640 is disposed below the color filter layer 430. The optical sensor 440 includes at least one pair of light receiving

portions

311 and 312 that detect light belonging to the same wavelength band.

It should be understood that those skilled in the art can easily change the embodiments to other embodiments without changing the technical idea and the essential features of the present invention in order to exemplify the above-described present invention. It is therefore to be understood that the above-described embodiments are illustrative in all respects, and not restrictive. In particular, the features of the present invention 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.

It is to be understood that the scope of the present invention is shown by the appended claims, rather than by the foregoing description, and all changes and modifications derived from the meaning and scope of the claims and the equivalent concepts thereof are included in the scope of the present invention.

Claims

1. A color illuminance sensor at a lower portion of a display, which is disposed at a lower portion of the display and measures brightness around the display, the display including a pixel generating light, a display retardation layer disposed at an upper portion of the pixel, and a display polarizing layer, wherein,

the color illumination sensor of the lower part of the display comprises:

a light selection layer having a first optical path and a second optical path that are optical paths for allowing display circularly polarized light generated by outside light incident from the outside of the display and unpolarized light generated by the pixels to travel;

a color filter layer disposed below the light selection layer, so that light passing through the first optical path and the second optical path passes through the color filter layer in different wavelength bands; and

a photosensor disposed below the color filter layer and having a first light receiving unit that detects light that has passed through the first optical path and a second light receiving unit that detects light that has passed through the second optical path,

the first light path allows all of the display circularly polarized light and the unpolarized light to pass through,

the second light path blocks circularly polarized light of the display and passes the unpolarized light,

the first light receiving unit and the second light receiving unit detect light of the same wavelength band.

2. The lower display color illumination sensor according to claim 1,

the light selective layer includes:

a sensor retardation layer for circularly polarized light incident on the display and having orthogonal slow and fast axes;

a first sensor polarizing light layer located at a lower portion of the sensor retardation layer, having a polarizing optical axis inclined at a first angle with respect to the slow axis; and

a second sensor polarizing light layer located at a lower portion of the sensor retardation layer and having a polarizing axis inclined at a second angle with respect to the slow axis,

the sensor retardation layer and the first sensor polarizing layer form the first optical path,

the sensor retardation layer and the second sensor polarizing layer form the second optical path.

3. The lower display color illumination sensor according to claim 2,

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

4. The lower display color illumination sensor according to claim 1,

the light selective layer includes:

a first sensor retardation layer for circularly polarized light incident on the display and having orthogonal first slow and fast axes;

a second sensor retardation layer for circularly polarized light incident on the display and having a second slow axis and a second fast axis orthogonal to each other; and

a sensor polarizing light layer located at a lower portion of the first sensor retardation layer and the second sensor retardation layer and having a polarization optical axis inclined at a first angle with respect to the first slow axis,

the first slow axis and the second slow axis are orthogonal,

the first sensor retardation layer and the sensor polarizing layer form the first optical path,

the second sensor retardation layer and the sensor polarizing layer form the second optical path.

5. The lower display color illumination sensor according to claim 4,

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

6. The lower display color illumination sensor according to claim 1,

the light selective layer includes:

a second sensor retardation layer for circularly polarized light incident on the display and having a second slow axis and a second fast axis orthogonal to each other;

a first sensor polarizing light layer located at a lower portion of the first sensor retardation layer and the second sensor retardation layer and having a polarizing optical axis inclined at a second angle with respect to the first slow axis; and

a second sensor polarizing light layer located at a lower portion of the first sensor retardation layer and the second sensor retardation layer and having a polarization optical axis inclined at a first angle with respect to the first slow axis,

the first slow axis and the second slow axis are orthogonal.

7. The lower display color illumination sensor according to claim 6,

a plurality of the first sensor delay layers and a plurality of the 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 a second plane.

8. The lower display color illumination sensor according to claim 2, 4 or 6, wherein,

the first light receiving unit detects a first sensor linear polarized light generated from the display circular polarized light and a second sensor linear polarized light generated from the non-polarized light,

the second light receiving unit detects third sensor linear polarized light generated from the unpolarized light.

9. The lower display color illumination sensor according to claim 1,

the light selective layer includes:

a sensor polarizing light layer located at a lower portion of the sensor retardation layer and having a polarizing axis inclined at a second angle with respect to the slow axis,

the sensor retardation layer and the sensor polarizing layer are provided only on the upper portion of the second light receiving unit.

10. The lower display color illumination sensor according to claim 1,

the color filter layer is composed of a plurality of repeated filter units, each filter unit is composed of 2N multiplied by N color filters, each filter unit comprises 2N same color filters, N and N are natural numbers which are larger than or equal to 1, and N is the type of the color filter.

11. The lower display color illumination sensor according to claim 10,

in the filter unit, the first light receiving unit is disposed below n filters of the 2n filters of the same color, and the second light receiving unit is disposed below the remaining n filters of the same color, respectively.

12. The lower display color illumination sensor according to claim 11,

in the filtering unit, two filters with the same color are arranged in contact with each other.

13. The lower display color illumination sensor according to claim 11,

in the filtering unit, two filters with the same color are arranged at intervals.

14. The lower display color illumination sensor according to any one of claims 10 to 13,

the light sensor measures the brightness of light of N different wave bands through N color filters.

15. The lower display color illumination sensor according to claim 14,

the first light receiving parts and the second light receiving parts measure the brightness of light emitted from a sensor detection region defined by a lower surface of the display,

the plurality of measurements are used to calculate an average brightness of light exiting the sensor detection area.