KR102101865B1 - Camera apparatus - Google Patents

Abstract

The TOF camera apparatus according to an embodiment of the present invention includes a light output unit for outputting patterned light, a plurality of pixels each including a first reception unit and a second reception unit, and output from the light output unit And an operation unit for calculating the distance of the object using the difference between the amount of light input to the first receiving unit and the second receiving unit, and an optical input unit to which the reflected light is input. The pattern conforms to at least one of the arrangement, area, and shape of a plurality of pixels of the light input unit.

Description

Camera device {CAMERA APPARATUS}

The present invention relates to a camera device, and more particularly, to a depth information of a TOF (Time of Flight) camera device.

Technology for obtaining a 3D image using a photographing apparatus has been developed. Depth map is required to acquire a 3D image. Depth information is information indicating a distance in space, and indicates perspective information of another point with respect to one point of a 2D image.

One of the methods of acquiring depth information is a method of projecting IR (Infrared) structured light onto an object, and extracting depth information by analyzing light reflected from the object. According to the IR structured light system, there is a problem that it is difficult to obtain a desired level of depth resolution for a moving object.

As a technology that replaces the IR structured light system, the TOF (Time of Flight) method is drawing attention. According to the TOF method, the distance from the object is calculated by measuring the flight time, that is, the time when the light is reflected by shooting. The TOF camera using the TOF method has a problem of low light efficiency and large noise.

The technical problem to be achieved by the present invention is to provide a TOF camera device for extracting depth information.

A camera device according to an embodiment of the present invention includes a plurality of pixels, each of which includes a first receiving unit and a second receiving unit, the light output unit outputting patterned light, and output from the light output unit It includes a light input unit for receiving the reflected light after the object, and a calculation unit for calculating the distance of the object using the difference in the amount of light input to the first receiving unit and the second receiving unit, the pattern of the patterned light Is dependent on at least one of the arrangement, area, and shape of a plurality of pixels of the light input unit.

The light output unit may include a light source and a light conversion unit that modulates light output from the light source.

The light conversion unit may include at least one of a diffractive optical element (DOE) patterning light, a hologram optical element (HOE), and a computer generated hologram (CGH). .

The light conversion unit may further include at least one of a focusing lens for focusing light output from the light source, and a reflecting member for adjusting a path of light.

Further comprising a light control unit for controlling the modulation (modulation) of the light output by the light output unit, the light control unit may adjust the amount of light by using the information on the distance of the object received from the operation unit.

According to an embodiment of the present invention, the light efficiency is increased, and thus depth information of a long distance can be extracted, and a signal to noise ratio (SN ratio) can be improved. In addition, power consumption can be reduced due to high light efficiency, and a light source unit can be implemented in a small size.

1 is a block diagram of a TOF camera device according to an embodiment of the present invention.
2 is a block diagram of an optical output unit of a TOF camera device according to an embodiment of the present invention.
3 is a structure of an optical input unit of a TOF camera device according to an embodiment of the present invention.
4 to 6 are diagrams illustrating a method of calculating a distance of an object by a calculation unit of a TOF device according to an embodiment of the present invention.
7 shows an example of an optical output unit of a TOF camera device according to an embodiment of the present invention.
8 is a cross-sectional view of the light output unit of FIG. 7.
9 shows another example of a light output unit of a TOF camera device according to an embodiment of the present invention.
10 illustrates patterned light output from the light output unit, and FIG. 11 illustrates a pattern of light input from the light input unit.
12 is a flowchart illustrating a method of adjusting the amount of light in a TOF camera device according to an embodiment of the present invention.

The present invention can be applied to various changes and can have various embodiments, and specific embodiments will be illustrated and described in the drawings. However, this is not intended to limit the present invention to specific embodiments, and should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention.

Terms including ordinal numbers such as second and first may be used to describe various components, but the components are not limited by the terms. The terms are used only for the purpose of distinguishing one component from other components. For example, the second component may be referred to as a first component without departing from the scope of the present invention, and similarly, the first component may also be referred to as a second component. The term and / or includes a combination of a plurality of related described items or any one of a plurality of related described items.

When an element is said to be "connected" or "connected" to another component, it is understood that other components may be directly connected to or connected to the other component, but other components may exist in the middle. It should be. On the other hand, when a component is said to be "directly connected" or "directly connected" to another component, it should be understood that no other component exists in the middle.

The terms used in this application are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "include" or "have" are intended to indicate the presence of features, numbers, steps, actions, components, parts or combinations thereof described herein, one or more other features. It should be understood that the existence or addition possibilities of fields or numbers, steps, operations, components, parts or combinations thereof are not excluded in advance.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person skilled in the art to which the present invention pertains. Terms such as those defined in a commonly used dictionary should be interpreted as having meanings consistent with meanings in the context of related technologies, and should not be interpreted as ideal or excessively formal meanings unless explicitly defined in the present application. Does not.

Hereinafter, exemplary embodiments will be described in detail with reference to the accompanying drawings, but the same or corresponding components are assigned the same reference numbers regardless of reference numerals, and overlapping descriptions thereof will be omitted.

1 is a block diagram of a TOF camera device according to an embodiment of the present invention, FIG. 2 is a block diagram of a light output unit of a TOF camera device according to an embodiment of the present invention, and FIG. 3 is a block diagram of an embodiment of the present invention It is a structure of the optical input unit of the TOF camera device, and FIGS. 4 to 6 are diagrams illustrating a method of calculating a distance of an object by the operation unit of the TOF device according to an embodiment of the present invention.

Referring to FIG. 1, the TOF camera apparatus 100 includes an optical output unit 110, an optical control unit 120, an optical input unit 130, and a calculation unit 140.

The light output unit 110 outputs patterned light. Here, the patterned light may be infrared (IR) light. Referring to FIG. 2, the light output unit 110 includes a light source 112 and a light conversion unit 114. The light source may include at least one laser diode or light emitting diode (LED) that projects infrared light. Also, the light conversion unit 114 may modulate light output from the light source 112. The light conversion unit 114 may, for example, pulse modulate or phase modulate the light output from the light source 112. Accordingly, the light output unit 110 may output by blinking the light source at a predetermined interval.

Referring back to FIG. 1, the light controller 120 controls modulation of light output from the light output unit 110. For example, the light control unit 120 may control pulse or phase modulation of light. The light controller 120 may control pulse or phase modulation of light according to a criterion preset by the user. For example, the light controller 120 may control pulse or phase modulation of light according to the brightness around the TOF camera device. The light control unit 120 may further control pulse or phase modulation of light by reflecting the operation result of the operation unit 140. Details of this will be described later.

Meanwhile, the light input unit 130 receives light reflected from an object after being output from the light output unit 110. The optical input unit 130 may convert the received light into an electrical signal. The optical input unit 130 may be an image sensor including a photo diode or a complementary metal-oxide semiconductor (CMOS). Referring to FIG. 3, the light input unit 130 includes a plurality of pixels 132 arranged. Each pixel may include an In Phase receiving unit 132-1 and an Out Phase receiving unit 132-2. 4, the In Phase receiving unit 132-1 is activated while the light source is turned on, and the Out Phase receiving unit 132-2 can be activated while the light source is turned off. As described above, when the In Phase receiving unit 132-1 and the Out Phase receiving unit 132-2 are activated with a time difference, a difference occurs in the amount of light received according to the distance to the object. For example, when the object is directly in front of the TOF camera device (that is, when the distance = 0), as shown in FIG. 5, since the time it takes for light to be reflected after the light is output from the light output unit 110 is 0, The flashing cycle of the light source is the receiving cycle of light as it is. Accordingly, only the In Phase receiving unit 132-1 receives light, and the Out Phase receiving unit 132-2 cannot receive light. As another example, when the object is located at a predetermined distance from the TOF camera device, as shown in FIG. 6, since light is output from the light output unit 110 and it takes time to reflect on the object, the flashing period of the light source is received by the light It is different from the period. Accordingly, a difference occurs in the amount of light received by the In Phase receiving unit 132-1 and the Out Phase receiving unit 132-2.

Referring back to FIG. 1, the calculating unit 140 calculates the distance of the object using the difference in the amount of light input to the In Phase receiving unit 132-1 and the Out Phase receiving unit 132-2.

According to an embodiment of the present invention, the pattern of the patterned light output from the light output unit 110 depends on at least one of an arrangement, area, and shape of a plurality of pixels. That is, the light output unit 110 outputs light patterned differently according to the effective surface of the pixel of the light input unit 130, thereby increasing the intensity of light incident on the pixel with the same amount of light. Accordingly, it is possible to increase the efficiency of the input light with respect to the output light amount.

7 shows an example of a light output unit of the TOF camera apparatus according to an embodiment of the present invention, FIG. 8 is a cross-sectional view of the light output unit of FIG. 7, and FIG. 9 is a view of the TOF camera apparatus according to an embodiment of the present invention Another example of the light output section is shown. In addition, FIG. 10 illustrates patterned light output from the light output unit, and FIG. 11 illustrates pattern of light input from the light input unit.

7 to 8, the light output unit 700 includes a light source 710, a collimating lens 720 and a patterning element 730.

The light source 710 may be, for example, a light emitting diode having at least one laser diode (LD), light emitting diode (LED), or multi-cell structure.

In addition, the focusing lens 720 focuses light from the light source 710. The patterning element 730 patterns light passing through the focusing lens 720. The patterning element 730 may include, for example, at least one of a diffractive optical element (DOE), a hologram optical element (HOE), and a computer generated hologram (CGH). have.

Referring to FIG. 9, the light output unit 700 may further include a reflective member 740 that adjusts a path of light. The reflective member 740 may include, for example, at least one mirror. When the reflective member 740 is further disposed between the light source 710 and the patterning element 730, the TOF camera device of various sizes and shapes may be implemented by adjusting a path of light output from the light source 710. The focusing lens 720, the patterning element 730, and the reflective member 740 may be a part of the light conversion unit 114 of FIG. 2.

Meanwhile, referring to FIGS. 10 and 11, the light output unit of the TOF camera apparatus according to an embodiment of the present invention outputs patterned light using a patterning element, and the light input unit receives patterned light .

For example, as shown in FIGS. 10 (a) and 11 (a), when the light output unit outputs the dot pattern light, the dot pattern light may be input to the light input unit. Alternatively, when the light output unit outputs light of a lattice pattern and a linear pattern as shown in FIGS. 10 (b), 11 (b), 10 (c), and 11 (c), the light input unit may also be provided with a lattice pattern or a straight pattern. Light can be input.

At this time, the light output unit may output light having a pattern corresponding to an effective surface of a pixel of the light input unit. That is, the pattern of light output from the light output unit may be in accordance with at least one of the pixel arrangement, area, and shape of the light input unit. For example, the pattern of the light output by the light output unit may vary according to at least one of the pixel arrangement, area, and shape of the light input unit.

 As described above, when the light output unit outputs light having a pattern matching the pixels of the light input unit, it is possible to increase the density of light input to the effective surface of the pixel. That is, high light efficiency can be obtained by using the same amount of light. Accordingly, the extraction distance of the depth information can be widened, and the signal to noise ratio (SN ratio) can be improved. In addition, due to the improvement of light efficiency, low-power driving is possible, and by reducing the number of light sources, a compact and lightweight TOF camera device can be implemented.

On the other hand, the TOF camera apparatus according to an embodiment of the present invention can adjust the amount of light using the calculation result of the calculation unit.

12 is a flowchart illustrating a method of adjusting a light amount of a TOF camera device according to an embodiment of the present invention.

Referring to FIG. 12, the operation unit 140 of the TOF camera apparatus compares the amount of light between the In Phase receiving unit and the Out phase receiving unit (S1200), and measures the distance between the object and the camera based on the difference in the amount of light (S1210). For example, the calculating unit 140 may determine that the distance of the object is greater as the light amount of the Out Phase receiving unit is greater than the light amount of the In Phase receiving unit.

Then, the calculation unit 140 transmits the measured distance information to the light control unit 130 (S1220), and the light control unit 130 uses the distance information received from the calculation unit 140, the amount of light of the light output unit 110 It controls (S1230).

For example, the light control unit 130 may reduce the amount of light as the object is closer to the TOF camera device, and increase the amount of light as it is farther away. The amount of light can be controlled by the intensity of light output from the light source. That is, the closer the object is to the TOF camera device, the lower the intensity of the output light, and the greater the distance, the higher the intensity of the light.

Alternatively, the amount of light may be controlled by pulse modulation or phase modulation. For example, the closer the object is to the TOF camera device, the slower the flashing cycle of the light source may be, and the farther it is, the faster the flashing cycle of the light source may be.

At this time, the controller 130 may control the amount of light based on an average value, an intermediate value, and the like of the distance extracted from all pixels.

As described above, when the light control unit 130 adjusts the light amount using the calculation result of the operation unit 140, power consumption can be reduced by reducing the light amount when the object is in a close position. And, when the object is in a distant position, accurate depth information can be extracted by increasing the amount of light.

Although described above with reference to preferred embodiments of the present invention, those skilled in the art variously modify and change the present invention without departing from the spirit and scope of the present invention as set forth in the claims below. You can understand that you can.

100: TOF camera device
110: light output
120: light control
130: optical input
140: operation unit
700: light output
710: light source
720: focus lens
730: patterning element
740: reflective member

Claims (5)

A light output unit that outputs patterned light,
An optical input unit including a plurality of pixels, each of which includes a first receiving unit and a second receiving unit, and after which light reflected from an object is output after being output from the optical output unit; and
It includes a calculation unit for calculating the distance of the object using the difference in the amount of light input to the first receiving unit and the second receiving unit,
The patterned pattern of light is a camera device according to at least one of an arrangement, area, and shape of a plurality of pixels of the light input unit. According to claim 1,
The light output unit
A camera device comprising a light source and a light conversion unit that modulates light output from the light source. According to claim 2,
The light conversion unit is a camera device comprising at least one of a diffractive optical element (DOE) patterning light, a hologram optical element (HOE) and a computer generated hologram (CGH) . According to claim 3,
The light conversion unit further includes at least one of a focusing lens for focusing light output from the light source, and a reflecting member for adjusting a path of light. According to claim 1,
Further comprising a light control unit for controlling the modulation (modulation) of the light output by the light output unit,
The light control unit is a camera device that adjusts the amount of light using information on the distance of the object received from the operation unit.

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