KR102160739B1 - Proximity sensor apparatus, display apparatus and distance image system - Google Patents

Abstract

The present invention relates to a proximity sensor device capable of preventing interference by internal reflected light, a display device, and a distance image system, comprising: a light emitting unit capable of emitting irradiation light for distance sensing; A light receiving unit capable of receiving reflected light reflected from the object by the irradiation light; And a blocking member installed on the light receiving unit and blocking internal reflected light emitted from the light emitting unit and reflected from the inside by the displayer.

Description

Proximity sensor apparatus, display apparatus, and distance image system TECHNICAL FIELD

The present invention relates to a proximity sensor device, a display device, and a distance image system, and more particularly, to a proximity sensor device capable of preventing interference by internal reflected light, a display device, and a distance image system.

In a smart device such as a smart phone or a smart pad, various proximity sensor devices may be installed under the display in order to measure the distance of a spaced object such as a face, hand, or hair.

1 is a cross-sectional view showing a conventional proximity sensor device installed under such a display 3.

As shown in FIG. 1, a conventional proximity sensor device is installed under a display 3 such as an LCD or OLED, and a light emitting unit 1 capable of emitting irradiation light L1 for distance sensing And, the light receiving unit 2 capable of receiving the reflected light L2 reflected from the object M by the irradiation light L1, and the intensity difference or time difference between the irradiation light L1 and the reflected light L2, or TOF It may include a distance measuring unit 4 for measuring the distance to the object (M) using (time of flight) or the like.

For example, when the object M has a simple shape such as a plane or a face, the distance measurement of the object M is when the irradiation light L1 emits light of a certain intensity, the amount of reflected light L2 is It is a function of the distance between the object M and the light emitting unit 1, and in general, the shorter the distance between the object M and the light emitting unit 1, the stronger the reflected light L2 is. From this, the object M ) Can be estimated. To measure the distance of the object M having a more complex shape, the light emitting unit 1 and the object M are measured by irradiating the light emitting unit 1 at a specific time and measuring the change over time of the reflected light L1 reflected from the object. , TOF (Time of flight) method of measuring the distance between the light-receiving units 2, etc.

Here, the light-emitting unit 1 may include, for example, an LED that generates the irradiation light L1 of 850 nanometers or 940 nanometers, and the light-receiving part 2 is the reflected light reflected from the object M. A photodiode or the like capable of receiving L2) may be applied.

However, such a conventional proximity sensor device, as shown in FIG. 1, is installed under the displayer 3 installed on a smart phone, and is generated in the light emitting unit 1, but the displayer 3 A crosstalk phenomenon occurs in which the internally reflected light L3 reflected on the surface of the displayer 3 is received by the light receiving unit 2, which does not pass through, and thus acts as noise when measuring a distance.

In addition, the light-receiving unit 2 is spaced apart from the display 3, and the separation distance must be constant, but the internal temperature varies according to the external temperature or operating time, so that the crosstalk phenomenon varies according to the separation distance. there was.

4 is a graph showing a signal shape for 30 minutes after the operation of the conventional proximity sensor device of FIG. 1.

As shown in FIG. 4, since the conventional proximity sensor device gradually narrows in a state where the separation distance is wide for 30 minutes after operation, it can be seen that the crosstalk phenomenon gradually decreases.

Therefore, the conventional proximity sensor device has many problems, such as greatly inferior in product precision and reliability due to interference caused by crosstalk for a certain period of time after operation.

The present invention has high space utilization because a bezel area is unnecessary, and even if it is installed at the bottom of the screen, it is possible to prevent a crosstalk phenomenon or a cracker phenomenon of the screen, and to greatly improve durability and precision even in thermal deformation or external impact. An object is to provide a proximity sensor device, a display device, and a distance image system. However, these problems are exemplary, and the scope of the present invention is not limited thereby.

Proximity sensor device according to the idea of the present invention for solving the above problem, a light emitting unit capable of emitting irradiation light for distance sensing; A light receiving unit capable of receiving reflected light reflected from the object by the irradiation light; And a blocking member installed on the light receiving unit and blocking internal reflected light emitted from the light emitting unit and reflected from the inside by the displayer.

In addition, according to the present invention, the light receiving unit may be installed below the displayer to be spaced apart from the displayer by a first distance.

In addition, according to the present invention, the blocking member is a black material capable of absorbing the internal reflected light, is formed at the same height as the first separation distance so that the top surface can be in close contact with the displayer, and the impact with the displayer It may be made of an elastic material to buffer the.

In addition, according to the present invention, the blocking member may have a through window formed therein, and may be formed in a wall shape surrounding the light receiving unit.

Further, according to the present invention, the blocking member may have an inclined surface inclined at a first inclination angle therein.

In addition, according to the present invention, a first filter that is installed in the light emitting path of the light emitting unit and passes only wavelengths in the non-interference band so that the irradiation light or the interference light reflected from the object does not interfere with the transistor part of the display; It may contain more.

Further, according to the present invention, the wavelength of the non-interference band may be 1.2 micrometers to 1.4 micrometers.

In addition, according to the present invention, the first filter may include a component included in the transistor portion of the display.

In addition, according to the present invention, the first filter is selected from at least one of a silicon filter, a band pass filter on glass, a silicon on glass, and combinations thereof. It can be done by doing.

In addition, the proximity sensor device according to the present invention may further include a second filter installed in the light receiving path of the light receiving unit and passing only the non-interference band wavelength so as to receive only the non-interference band wavelength. .

On the other hand, the display device according to the spirit of the present invention for solving the above problems, at least one transistor portion is formed display; And a proximity sensor device installed below the displayer, wherein the distance sensing sensor includes: a light emitting unit capable of emitting irradiation light for distance sensing; A light receiving unit capable of receiving reflected light reflected from the object by the irradiation light; A distance measuring unit for measuring a distance to the object by using an intensity ratio of the irradiated light and the reflected light or a time of flight (TOF) between the irradiated light and the reflected light; And the above-described proximity sensor device.

In addition, according to the present invention, the display is an LCD display or an OLED display, and the transistor is at least one source, a drain, and a gate for driving an active layer of the display. ) Can be included.

According to an embodiment of the present invention made as described above, a crosstalk phenomenon can be prevented by using a blocking member, and malfunction of the display due to interference light such as a flicker phenomenon can be prevented by using the first filter or the second filter. A preventable proximity sensor device and a display device can be implemented. Of course, the scope of the present invention is not limited by these effects.

1 is a cross-sectional view showing a conventional proximity sensor device.
2 is a cross-sectional view illustrating a proximity sensor device and a display device according to some embodiments of the present invention.
3 is a cross-sectional view illustrating a proximity sensor device and a display device according to some other embodiments of the present invention.
4 is a graph showing a signal shape for 30 minutes after the operation of the conventional proximity sensor device of FIG. 1.
5 is a graph showing a signal shape for 30 minutes after the operation of the proximity sensor device of the present invention of FIG. 2.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, and the following embodiments make the disclosure of the present invention complete, and the scope of the invention to those of ordinary skill in the art. It is provided to fully inform you. In addition, in the drawings for convenience of description, the size of the components may be exaggerated or reduced.

2 is a cross-sectional view illustrating a proximity sensor device 100 and a display device according to some embodiments of the present invention.

First, as illustrated in FIG. 2, the proximity sensor device 100 according to some embodiments of the present invention may include a light emitting unit 10, a light receiving unit 20, and a blocking member 50.

For example, as shown in FIG. 2, the light emitting unit 10 is a device capable of emitting irradiation light L1 for distance sensing, and an LED capable of generating general light may be applied. However, the light-emitting unit 10 is not necessarily limited thereto, and various types of light-emitting devices that generate light of various wavelength bands may be applied.

In addition, for example, as shown in FIG. 2, the light receiving unit 20 is a device capable of receiving the reflected light L2 reflected from the object M by the irradiation light L1, and has various types of photos. Diode, thermopile, pyroelectric device, photoconductor, etc. can be applied.

In addition, for example, as shown in FIG. 2, the blocking member 50 is installed on the upper surface of the light receiving unit 20 and is radiated from the light emitting unit 10 to be emitted from the inside by the display 30. It may be a structure that blocks the reflected internal reflection light L3.

Here, the light receiving unit 20 may be installed below the display 30 to be spaced apart from the display 30 by a first distance, and the blocking member 50 may include the internal reflected light L3 ) Is a gray or black material that can absorb and block, and is formed at the same height as the first separation distance so that the top surface can be in close contact with the display 30, and can buffer the impact with the display 30 It may be made of an elastic material such as rubber, silicone, urethane or foam resin.

More specifically, for example, as shown in FIG. 2, the blocking member 50 has a through window formed therein, and is formed in the form of a ring-shaped wall surrounding the light receiving unit 20, and the blocking member 50 The member 50 may have an inclined surface 51 inclined at the first inclination angle K1 therein.

Here, the first inclination angle K1 is based on the main optical axis of the display 30, and if the angle is too small, the effect of blocking the internal reflected light L3 is high, but instead the normal reflected light L2 ) May decrease the light-receiving amount or the light-receiving range, and if the angle is too large, the light-receiving amount or the light-receiving range of the reflected light L2 may be increased, but the effect of blocking the internal reflected light L3 may be reduced.

Accordingly, as a result of repeated experiments, the first inclination angle K1 may be 35 degrees to 55 degrees.

Therefore, the crosstalk phenomenon can be prevented by using the blocking member 50 capable of blocking the internal reflected light L3, and detection of thermal deformation or external impact can be performed by using the buffering action of the blocking member 50. It can greatly improve the precision and durability of the parts.

5 is a graph showing a signal shape for 30 minutes after the operation of the proximity sensor device 30 of the present invention of FIG. 2.

In addition, as shown in FIG. 5, when the intensity of the signal received for 30 minutes after operation is compared to that of FIG. 4, it is relatively constant, and the crosstalk phenomenon disappears, so that an accurate proximity detection signal is received immediately after operation, and more accurately and quickly. It can operate normally.

3 is a cross-sectional view illustrating a proximity sensor device 200 and a display device according to some other embodiments of the present invention.

As shown in FIG. 3, in general, the displayer 3 to which a thin film transistor (TFT), a low temperature poly-silicon (LTPS), etc. is applied is at least for driving the active layer A made of silicon doped with a low concentration. A portion of the transistor T including one source S, a drain D, and a gate G may be included.

The irradiation light L1 generated from the light emitting unit 1 or the interference light L4 reflected from the object M is applied to the gate G and the active layer A for activating the active layer A. It is absorbed and intermittently excites the active layer (A) by a photoelectric effect, that is, a photo conductive effect, and the irradiation light (in the On or Off) state of the display 3 ( There is a problem in that a flicker phenomenon in which the screen flickers according to the on or off of L1).

Therefore, the existing sensor for distance detection operates with the LCD or OLED completely turned off, or is installed on the edge (bezel) that does not overlap with the LCD or OLED in the area where the sensor for distance detection is attached. Therefore, there is a problem that space utilization is deteriorated due to such unnecessary bezel area.

In addition, the distance image sensor, which is another of the conventional distance sensing sensors, is composed of one light emitting unit 1, the light receiving unit 2 having a plurality of pixels, and a distance measuring unit 4, and the lower part of the LCD or OLED. Even if it is installed in the device, it causes flicker, so these problems could not be solved.

As illustrated in FIG. 3, the proximity sensor device 200 according to some other embodiments of the present invention may further include a first filter F1 and a second filter F2.

For example, as shown in FIG. 3, the first filter F1 is installed in the light emitting path of the light emitting unit 10, and the interference light reflected from the irradiation light L1 or the object M ( L4) may be a filter that passes only a wavelength in a non-interference band so that it does not interfere with the transistor T portion of the display 30.

For example, the non-interference band wavelength of the first filter F1 is a near-infrared band wavelength, and interference with the gate (G) and the active layer (A) for activating the active layer (A) of the display 30 to be described later It may be a wavelength in a non-interference band excluding a wavelength in a short wavelength band that can be used.

More specifically, for example, the wavelength of the non-interference band may be in the range of 1.1 micrometers to 1.4 micrometers. In the TFT used to control the light emission of pixels in LCD or OLED, an active area (A) is formed using a poly-silicon. In addition, poly-silicon reacts to light with a wavelength of less than 1.1 micrometers and does not react to light of 1.1 micrometers or more.

Therefore, the wavelength in the non-interference band (1.2um ~ 1.4um) in the near infrared rays passes through without being absorbed by the gate (G) and the active layer (A) of the transistor (T) portion of the display 30 Therefore, it does not affect the active layer (Active area, A) activated by the gate (G), and prevents malfunctions such as flickering of the screen during operation of the sensor even in all cases such as screen on/off. can do.

The first filter F1 may be a silicon filter, a band pass filter on glass, or a silicon on glass filter. Here, the first filter (F1) is the transistor (T) portion of the display 30 to absorb light of a wavelength that may interfere with the transistor (T) portion of the display 30 It is preferable to include the ingredients contained in.

The first filter F1 is capable of adjusting a band of wavelengths that can be passed according to a material characteristic, a lamination characteristic, a manufacturing method, etc., and such a filter manufacturing method is already known and widely used. Therefore, a detailed description will be omitted.

In addition, for example, as shown in Figure 3, the second filter (F2) is installed in the light receiving path of the light receiving unit 20, the non-interference band wavelength so as to receive only the non-interference band wavelength It may be a filter that only passes.

Here, the second filter F2 may be a filter that passes only the wavelength of the non-interference band so that only the wavelength of the non-interference band is received from the reflected light L2 reflected from the object M.

For example, the non-interference band wavelength of the second filter F2 is a non-interference band wavelength, and is reflected from the irradiated light L1 passing through the first filter F1 or the object M. Among the reflected lights L2, a wavelength of a non-interference band excluding a wavelength of a short wavelength band that activates the active layer A of the displayer 30 to be described later may be used.

In addition, when the subject of the sensor is an object such as skin or hair, it is required to have a high surface reflectance. Since the skin reflectance decreases rapidly above 1.5 micrometers, it is recommended to select light in the wavelength band below this for the purpose of the proximity sensor. desirable.

More specifically, for example, the wavelength of the non-interference band may be in the range of 1.2 micrometers to 1.4 micrometers.

Therefore, since the light-receiving unit 20 can receive only such a specific wavelength band, it is possible to measure the distance more accurately by excluding the light of the other wavelength band.

The second filter F2 may be a silicon filter, a band pass filter on glass, or a silicon on glass filter.

The second filter F2 is capable of adjusting a band of wavelengths that can be passed according to a material characteristic, a lamination characteristic, a manufacturing method, etc., and such a filter manufacturing method is already known and widely used. Therefore, a detailed description will be omitted.

In addition, the second filter F2 may be substantially the same as the first filter F1. However, the present invention is not limited thereto, and for example, the wavelength band of the first filter F1 is formed relatively narrow to reduce the flicker phenomenon, and instead, the wavelength band of the second filter F2 is formed relatively wide. It is also possible to widen the sensing area or omit the second filter F2.

Therefore, by using the first filter (F1) or the second filter (F2), it is possible to prevent malfunction of the displayer 30 due to interference light such as a flicker phenomenon, and the second filter (F2) By using the reflected light from which the interference light is excluded, more precise distance measurement is possible.

Meanwhile, in the display device according to some embodiments of the present invention, the display device 30 having at least one transistor (T) portion formed thereon and the above-described proximity sensor device 100 installed below the displayer 30 ) 200 may be included.

Here, as shown in FIG. 3, the displayer 30 is, the displayer 30 is an LCD display or an OLED display, and the transistor T is an active layer of the displayer 30 ( It may include at least one source (S) (source), a drain (D) (drain) and a gate (G) (gate) for driving A).

In addition, the distance sensing sensor 100 includes a light emitting unit 10 capable of emitting a distance sensing irradiation light L1, and a reflected light L2 reflected from the object M by the irradiation light L1. ), and an intensity ratio (intensity change) of the irradiated light L1 and the reflected light L2, or a TOF (time of flight) between the irradiated light L1 and the reflected light L2. ) To measure the distance to the object (M), and installed in the light emitting path of the light emitting portion 10, and reflected from the irradiation light (L1) or the object (M) The first filter (F1) passing only the non-interference band wavelength so that the interfering light L4 does not interfere with the transistor (T) portion of the display 30 and is installed in the light receiving path of the light receiving unit 20, And a second filter F2 that passes only the non-interference band wavelength so that only the non-interference band wavelength can be received.

Here, the proximity sensor device 100 may have the same configuration and role as the proximity sensor device according to some embodiments of the present invention described above. Therefore, detailed description is omitted.

In addition, the distance measuring unit 40 is a method of measuring the distance using a characteristic in which the intensity ratio of the irradiated light L1 and the reflected light L2 is a function of the distance to the object M, or the speed of light To calculate the TOF by measuring the time difference between the outgoing point of the irradiation light L1 and the receiving point of the reflected light L2 in consideration of, and converting the TOF into a distance, the distance to the object M is calculated. I can. This distance measurement method is already known and widely used. Therefore, detailed description is omitted.

Therefore, by using the near-infrared long-wavelength non-interference band wavelength, the interfering light L4 passes through the active layer A of the transistor T part of the display 30 without being absorbed. Since it does not affect the active layer A activated by the gate G, malfunctions such as a flicker phenomenon in which the screen flickers due to a sensor operation when the screen is turned on and off can be prevented in advance.

In addition, it is possible to measure a more precise distance by using the reflected light from which the interference light is excluded by using the second filter F2.

Meanwhile, the distance measuring sensors 100 and 200 of the present invention are not necessarily limited to the drawings, and various sensors such as a distance image sensor may be applied.

Meanwhile, the present invention may include a distance imaging system including the proximity sensor device of the present invention described above. The distance image system may be a system capable of generating image information indicating a distance using the proximity sensor device of the present invention.

Although the present invention has been described with reference to an embodiment shown in the drawings, this is only exemplary, and those of ordinary skill in the art will appreciate that various modifications and equivalent other embodiments are possible therefrom. Therefore, the true technical protection scope of the present invention should be determined by the technical spirit of the appended claims.

M: object
1, 10: light emitting unit
2, 20: light receiving unit
3, 30: displayer
4, 40: distance measuring unit
50: blocking member
51: slope
L1: irradiation light
L2: reflected light
L3: internally reflected light
L4: interference light
T: transistor
S: source
D: drain
G: gate
A: active layer
F1: first filter
F2: second filter
100, 200: proximity sensor device

Claims (13)

A light emitting unit capable of emitting irradiation light for distance sensing;
A light receiving unit capable of receiving reflected light reflected from an object by the irradiation light;
A blocking member installed on the light receiving unit and blocking internal reflected light emitted from the light emitting unit and reflected from the inside by the displayer; And
A first filter installed in the light emitting path of the light emitting unit and passing only a wavelength in a non-interference band so that the irradiated light or the interference light reflected from the object can pass without interfering with the transistor portion of the displayer; and
The first filter,
A proximity sensor device comprising a component included in the transistor portion of the display. The method of claim 1,
The light receiving unit,
A proximity sensor device installed below the displayer to be spaced apart from the displayer by a first distance. The method of claim 2,
The blocking member,
Proximity sensor made of a black material capable of absorbing the internal reflected light, formed at the same height as the first separation distance so that an upper surface can be in close contact with the display, and made of an elastic material to buffer an impact with the displayer Device. The method of claim 3,
The blocking member has a through window formed therein, and is formed in the form of a wall surrounding the light receiving unit. The method of claim 4,
The blocking member is a proximity sensor device having an inclined surface inclined at a first inclination angle therein. delete The method of claim 1,
The non-interference band wavelength is 1.2 micrometers to 1.4 micrometers. delete The method of claim 1,
The first filter is formed by selecting at least one of a silicon filter, a band pass filter on glass, a silicon on glass, and combinations thereof. The method of claim 1,
A second filter installed in the light-receiving path of the light-receiving unit and passing only the non-interference band wavelength so that only the non-interference band wavelength is received;
Further comprising a proximity sensor device. A display on which at least one transistor portion is formed; And
Includes; a proximity sensor device installed under the displayer,
The sensor for distance detection,
A light emitting unit capable of emitting irradiation light for distance sensing;
A light receiving unit capable of receiving reflected light reflected from an object by the irradiation light;
A distance measuring unit measuring a distance to the object; And
The proximity sensor device according to any one of claims 1, 2, 3, 4, 5, 7, 9, and 10;
Containing, a display device. The method of claim 11,
The displayer is an LCD display or an OLED display,
The transistor part includes at least one source, a drain, and a gate for driving an active layer Active of the display device. A distance imaging system comprising a proximity sensor device according to any one of claims 1, 2, 3, 4, 5, 7, 9 and 10.

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