Camera device

Abstract

The camera device according to an embodiment of the present invention includes an optical output unit that generates an output optical signal and irradiates an object therewith, an optical input unit that receives an input optical signal input after being reflected from the object, and a depth information generation unit that generates depth information of the object using the input optical signal input to the optical input unit. The optical output unit includes a light source that generates the output optical signal, and a beam splitter that splits the output optical signal generated by the light source into a first polarization component and a second polarization component that are different from each other. The first polarization component and the second polarization component are irradiated onto the object so as to be distinguishable from each other.

Description

Technical Field

[0001] The present invention relates to a camera device.

Background Art

[0002] 3D content is applied in many fields such as games, culture, education, manufacturing, and autonomous driving. To obtain 3D content, depth information (Depth Map) is required. Depth information is information indicating the distance in space and shows the perspective information of other points relative to a point in a 2D video. As methods for obtaining depth information, a method of projecting IR (Infrared) structured light onto an object, a method using a stereo camera, a TOF (Time of Flight) method, etc. are used.

[0003] To obtain depth information, the light output unit of the camera device generates an output optical signal and irradiates an object with it. The light input unit of the camera device receives the input optical signal reflected from the object. The depth information generation unit of the camera device generates the depth information of the object using the input optical signal input to the light input unit.

[0004] At this time, the light output unit can irradiate the object with the output optical signal of the point illumination pattern. Here, the point illumination pattern can mean a spot array shape separated at regular intervals within a predetermined area. The higher the number of spots per unit area, the higher the measurement resolution. However, if the distance between spots is short, interference between spots may occur, which may reduce the accuracy of the generated depth information.

Summary of the Invention

Problems to be Solved by the Invention

[0005] The technical problem to be achieved by the present invention is to provide a camera device capable of extracting depth information with high accuracy and resolution.

Means for Solving the Problems

[0006] A camera device according to an embodiment of the present invention includes a light output unit that generates an output optical signal and irradiates an object, a light input unit that receives an input optical signal input after being reflected from the object, and a depth information generation unit that generates depth information of the object using the input optical signal input to the light input unit. The light output unit includes a light source that generates the output optical signal, and a beam splitter that splits the output optical signal generated by the light source into a first polarization component and a second polarization component that are different from each other. The first polarization component and the second polarization component are irradiated onto the object so as to be distinguishable from each other.

[0007] The light output unit further includes a first phase retardation member that phase-retards the first polarization component, and a second phase retardation member that phase-retards the second polarization component. The first polarization component phase-retarded by the first phase retardation member and the second polarization component phase-retarded by the second phase retardation member may be irradiated onto the object so as to be distinguishable from each other.

[0008] One of the first polarization component and the second polarization component is a P polarization component, and the other is an S polarization component. The first polarization component is circularly polarized in a first direction by the first phase retardation member, and the second polarization component may be circularly polarized in a second direction different from the first direction by the second phase retardation member.

[0009] The first phase retardation member and the second phase retardation member may each phase-retard the first polarization component and the second polarization component by 90 degrees.

[0010] The first polarization component is irradiated onto the object in a first spot array shape, the second polarization component is irradiated onto the object in a second spot array shape, and the first spot array may be arranged separated from the second spot array between the second spot arrays.

[0011] The first polarization component and the second polarization component may be irradiated onto the object simultaneously.

[0012] At least one of the first polarization component and the second polarization component split by the beam splitter may be reflected by a mirror and then irradiated onto the object.

[0013] Further included are a first optical element disposed on the path irradiated by the first polarization component and diffusing the first polarization component, and a second optical element disposed on the path irradiated by the second polarization component and diffusing the second polarization component, and at least one of the first optical element and the second optical element may be a diffractive optical element (DOE).

[0014] The light input unit receives the first polarization component input after being reflected from the object in a first time domain, and receives the second polarization component input after being reflected from the object in a second time domain that does not overlap with the first time domain, and the depth information generation unit may generate depth information of the object using the first polarization component and the second polarization component.

[0015] The depth information generation unit may generate the depth information using at least one of the phase difference and the time difference between the output optical signal and the input optical signal.

[0016] The output optical signal is structured light having a predetermined pattern, and the depth information generation unit may generate the depth information using the disparity of the structured light.

[0017] A camera device according to another embodiment of the present invention includes a light output unit that irradiates an object with an optical signal of a predetermined pattern composed of a plurality of points, a light input unit that receives the optical signal reflected from the object, and a depth information generation unit that generates depth information of the object using the disparity of the optical signal received by the light input unit. The light output unit includes a first optical system that irradiates the object with the optical signal having a first angle of view, and a second optical system that irradiates the object with the optical signal having a second angle of view smaller than the first angle of view. The light input unit includes a zoom optical system and an image sensor that are driven at either a first magnification or a second magnification higher than the first magnification. When the first optical system is driven, the zoom optical system is driven at the first magnification, and when the second optical system is driven, the zoom optical system is driven at the second magnification.

[0018] The camera device further includes a control unit that controls the light output unit, the light input unit, and the depth information generation unit. The first optical system may include a first light source and a first diffractive optical element (DOE) that diffuses the light output by the first light source at the first angle of view. The second optical system may include a second light source and a second diffractive optical element that diffuses the light output by the second light source at the second angle of view.

[0019] When the first light source is turned on, the control unit may control the zoom optical system to be driven at the first magnification, and when the second light source is turned on, the control unit may control the zoom optical system to be driven at the second magnification.

[0020] The first light source and the second light source output light of the same pattern. The light output by the first light source is radiated n*n times by the first diffractive optical element and irradiates the object. The light output by the second light source is radiated n*n times by the second diffractive optical element and irradiates the object. Here, n may be an integer of 2 or more.

[0021] The zoom optical system may include a zoom lens and an actuator that drives the zoom lens at either the first magnification or the second magnification.

[0022] The apparatus further includes a control unit that controls the light output unit, the light input unit, and the depth information generation unit, and the control unit may control so that either one of the first optical system and the second optical system is selectively driven.

[0023] When the generated depth information is equal to or less than a preset distance, the light output unit irradiates the object with the light signal having the first angle of view, and when the generated depth information exceeds the preset distance, the light output unit may irradiate the object with the light signal having the second angle of view.

[0024] A method for generating depth information of a camera device according to another embodiment of the present invention includes a step of irradiating an object with a light signal of a predetermined pattern composed of a plurality of points by a light output unit, a step of interlocking the light output unit and the light input unit, a step of receiving, by the light input unit, a light signal reflected from the object, and a step of generating depth information of the object using a disparity of the light signal received by the light input unit. The step of irradiating the light signal includes irradiating the object with either the light signal having the first angle of view or the light signal having a second angle of view smaller than the first angle of view by the light output unit. The step of interlocking the light output unit and the light input unit includes driving the zoom lens of the light input unit at a first magnification when the light output unit irradiates the object with the light signal having the first angle of view, and driving the zoom lens of the light input unit at a second magnification higher than the first magnification when the light output unit irradiates the object with the light signal having the second angle of view.

[0025] The step of irradiating the object with the optical signal may include the optical output unit selectively irradiating the object with the optical signal of the first angular field of view or the optical signal of the second angular field of view according to the generated depth information.

[0026] The step of irradiating the object with the optical signal may include the optical output unit irradiating the object with the optical signal of the first angular field of view when the generated depth information is less than or equal to a preset distance, and the optical output unit irradiating the object with the optical signal of the second angular field of view when the generated depth information exceeds the preset distance.

Advantages of the Invention

[0027] According to the embodiments of the present invention, since the number of spots per unit area can be maximally arranged, depth information can be extracted with high resolution. Also, according to the embodiments of the present invention, since the number of spots per unit area is maximized and the interference between spots is minimized, depth information can be extracted with high accuracy. According to the embodiments of the present invention, a camera device applicable to the extraction of depth information not only at a long distance but also at a short distance can be obtained. According to the embodiments of the present invention, since a high-pixel image sensor is not used, the power consumption and the amount of calculation of the entire camera device can be reduced.

Brief Description of the Drawings

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Embodiments for Carrying Out the Invention

[0049] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0050] However, the technical idea of the present invention is not limited to some of the described embodiments, and can be implemented in various different forms. As long as it is within the scope of the technical idea of the present invention, one or more of the components between the embodiments can be selectively combined, replaced, and used.

[0051] In addition, the terms (including technical and scientific terms) used in the embodiments of the present invention, unless specifically defined otherwise, can be interpreted as meanings generally understood by those with ordinary knowledge in the technical field to which the present invention belongs. Commonly used terms such as those defined in a dictionary can be interpreted in consideration of their meanings in the context of the related art.

[0052] Also, the terms used in the embodiments of the present invention are for the purpose of explaining the embodiments and are not intended to limit the present invention.

[0053] In this specification, the singular form can include the plural form unless otherwise specified in the context. When described as "at least one (or one or more) of A and (or) B, C", it may include one or more of all possible combinations of A, B, and C.

[0054] In addition, when explaining the components of the embodiments of the present invention, terms such as first, second, A, B, (a), (b), etc. can be used.

[0055] Such terms are merely for distinguishing the components from other components, and the essence, order, or procedure of the components are not limited by such terms.

[0056] Also, when a component is described as "connected", "coupled", or "joined" to another component, it includes not only the case where the component is directly connected, coupled, or joined to the other component, but also the case where the component is "connected", "coupled", or "joined" by still other components between the component and the other component.

[0057] Also, when it is described that it is formed or disposed “above or below” each component, “above or below” includes not only the case where two components are in direct contact with each other, but also the case where one or more other components are formed or disposed between the two components. Further, when expressed as “above or below”, it may include the meaning of not only the upper direction but also the lower direction with respect to one component.

[0058] The camera device according to an embodiment of the present invention may mean a camera that extracts depth information using a ToF (Time of Flight) function or a structured light method. Therefore, the camera device may be used interchangeably with a depth information extraction device, a three-dimensional information extraction device, etc., and when using the ToF function, it may also be used interchangeably with a ToF camera device, a ToF camera, etc.

[0059] FIG. 1 is a block diagram of a camera device according to an embodiment of the present invention, and FIG. 2 is a schematic cross-sectional view of the camera device according to an embodiment of the present invention. FIG. 3 is a diagram for explaining an output optical signal output by the camera device according to an embodiment of the present invention.

[0060] Referring to FIGS. 1 and 2, a camera device 1 according to an embodiment of the present invention includes an optical output unit 10, an optical input unit 20, a depth information generation unit 30, and a control unit 40.

[0061] The light output unit 10 irradiates an object after generating an output optical signal. At this time, the light output unit 10 can generate and output the output optical signal in the form of a pulse wave or a continuous wave. The continuous wave may be in the form of a sinusoid wave or a squared wave. By generating the output optical signal in the form of a pulse wave or a continuous wave, the camera device 1 can detect the time difference or phase difference between the output optical signal output from the light output unit 10 and the input optical signal input to the light input unit 20 after being reflected from the object. In this specification, the output light means the light output from the light output unit 10 and incident on the object, and the input light may mean the light output from the light output unit 10, reaching the object, and then being reflected from the object and input to the light input unit 20. From the perspective of the object, the output light can become the incident light, and the input light can become the reflected light.

[0062] Referring to FIG. 3(a), the light output unit 10 can generate optical pulses at a constant period. The light output unit 10 can generate an optical pulse having a predetermined pulse repetition period (t modulation ) and a predetermined pulse width (t pulse ).

[0063] Referring to FIG. 3(b), a certain number of optical pulses generated by the light output unit 10 can be grouped to form one phase pulse. The light output unit 10 can generate a phase pulse having a predetermined phase pulse period (t phase ) and a predetermined phase pulse width (t exposure ). The phase pulse width may also be called t illumination or t integration . Here, one phase pulse period (t phase ) can correspond to one sub-frame. The sub-frame may also be called a phase frame. The phase pulse periods can be grouped into a predetermined number. Four phase pulse periods (t phase) The method of grouping them may be called a 4-phase method. For eight cycles (t phase ) The method of grouping them may be called an 8-phase method.

[0064] Referring to FIG. 3(c), a certain number of phase pulses generated by the optical output unit 10 can be grouped to form one frame pulse. The optical output unit 10 can generate a frame pulse having a predetermined frame pulse period (t frame ) and a predetermined frame pulse width (t phase group(sub-frame group) ). Here, one frame pulse period (t frame ) can correspond to one frame. Therefore, when shooting an object at 10 FPS, the frame pulse period (t frame ) may be repeated 10 times per second. In the 4-phase method, one frame may include four sub-frames. That is, one frame is generated through four sub-frames. In the 8-phase method, one frame may include eight sub-frames. That is, one frame is generated through eight sub-frames.

[0065] In the above, for the sake of explanation, the terms of optical pulse, phase pulse, and frame pulse are used, but it is not limited thereto.

[0066] Referring to FIGS. 1 and 2 again, the optical output unit 10 may include a light source 100 and a lens assembly 110.

[0067] First, the light source 100 generates light. The light generated by the light source 100 may be infrared light with a wavelength of 770 to 3000 nm, or may be visible light with a wavelength of 380 to 770 nm. As the light source 100, a light emitting diode (LED) may be used, or it may have a form in which a plurality of light emitting diodes are arranged in a certain pattern. In addition to this, the light source 100 may include an organic light emitting diode (OLED) or a laser diode (LD). Alternatively, the light source 100 may be a VCSEL (Vertical Cavity Surface Emitting Laser). The VCSEL is one of the laser diodes that converts an electrical signal into an optical signal, and can output a wavelength of about 800 to 1000 nm, for example, a wavelength of about 850 nm or about 940 nm. The light source 100 repeats blinking (on / off) at regular time intervals to generate a pulsed or continuous wave output optical signal. The regular time interval may be the frequency of the output optical signal.

[0068] The lens assembly 110 can collect the light output from the light source 100 and output the collected light to the outside. The lens assembly 110 may be disposed above the light source 100 and separated from the light source 100. Here, the upper part of the light source 100 may mean the side from which light is output from the light source 100. The lens assembly 110 may include at least one lens. When the lens assembly 110 includes a plurality of lenses, each lens can be aligned with respect to the central axis to form an optical system. Here, the central axis may be the same as the optical axis of the optical system.

[0069] The lens assembly 110 may be housed or supported in the housing 120. According to an embodiment, the housing 120 may be coupled to a drive module (not shown), and the lens assembly 110 may move in the optical axis direction or a direction perpendicular to the optical axis by the drive module (not shown).

[0070] On the one hand, the optical input unit 20 receives light reflected from an object. For this purpose, the optical input unit 20 may include a lens assembly 130 that condenses the input light reflected from the object, a filter (not shown), and an image sensor 140 that converts the input light that has passed through the lens assembly 130 into an electrical signal. The lens assembly 130, the filter (not shown), and the image sensor 140 may be housed or supported in a housing 150. Although the housing 120 on the optical output unit 10 side and the housing 150 on the optical input unit 20 side are shown as being separated from each other, the present invention is not limited thereto, and the housing 120 on the optical output unit 10 side and the housing 150 on the optical input unit 20 side may be an integral housing.

[0071] The optical axis of the lens assembly 130 may be aligned with the optical axis of the image sensor 140. The filter (not shown) is disposed between the lens assembly 130 and the image sensor 140 and can filter light having a predetermined wavelength range. For example, the filter (not shown) can pass light in the wavelength band of the output light output by the optical output unit 10.

[0072] The image sensor 140 can receive an input optical signal in synchronization with the blinking period of the light source 100. Specifically, the image sensor 140 can receive light in phase and out of phase with the output optical signal output from the light source 100, respectively. That is, the image sensor 140 can repeatedly perform the step of receiving an input optical signal when the light source is on and the step of receiving an input optical signal when the light source is off. The image sensor 140 can generate an electrical signal corresponding to each reference signal using a plurality of reference signals having different phase differences from each other. The frequency of the reference signal may be set in the same manner as the frequency of the output optical signal output from the light source 100. Therefore, when the light source 100 generates an output optical signal at a plurality of frequencies, the image sensor 140 generates an electrical signal using a plurality of reference signals corresponding to each frequency. The electrical signal may include information regarding the amount of charge or voltage corresponding to each reference signal.

[0073] The reference signals according to the embodiments of the present invention may be four (C 1 ~C 4 , not shown). Each reference signal (C 1 ~C 4 ) has the same frequency as the output optical signal, but may have a phase difference of 90 degrees from each other. One of the four reference signals (C 1 ) may have the same phase as the output optical signal. The phase of the input optical signal is delayed by the distance that the output optical signal travels after being incident on the object and then reflected back. The image sensor 140 mixes the input optical signal and each reference signal respectively. As a result, the image sensor 140 can generate an electrical signal for each reference signal.

[0074] The image sensor 140 may be configured with a structure in which a plurality of pixels are arranged in a grid. The image sensor 140 may be a CMOS (Complementary Metal Oxide Semiconductor) image sensor or a CCD (Charge Coupled Device) image sensor. Further, the image sensor 140 may include a ToF sensor that receives IR light reflected from the object and measures the distance using time or phase difference. For example, each pixel may include an In phase reception unit that receives the input optical signal in the same phase as the waveform of the output light, and an Out phase reception unit that receives the input optical signal in the opposite phase to the waveform of the output light. When the In phase reception unit and the Out phase reception unit are activated with a time difference, a difference occurs in the amount of light received by the In phase reception unit and the Out phase reception unit depending on the distance to the object, and the distance to the object can be calculated using this difference.

[0075] The optical input unit 20 may be arranged side by side with the optical output unit 10. The optical input unit 20 may be arranged adjacent to the optical output unit 10. The optical input unit 20 may be arranged in the same direction as the optical output unit 10.

[0076] The depth information generation unit 30 can generate the depth information of the object using the input optical signal input to the optical input unit 20. For example, the depth information generation unit 30 can calculate the depth information of the object using the flight time from when the output optical signal output from the optical output unit 10 is reflected by the object until it is input to the optical input unit 20. For example, the depth information generation unit 30 calculates the phase difference between the output optical signal and the input optical signal using the electrical signal received from the image sensor 140, and calculates the distance between the object and the camera device 1 using the calculated phase difference.

[0077] Specifically, the depth information generation unit 30 can calculate the phase difference between the output optical signal and the input optical signal using the charge amount information of the electrical signal.

[0078] As discussed above, four electrical signals can be generated for each frequency of the output optical signal. Therefore, the depth information generation unit 30 can calculate the phase difference (t d ) between the output optical signal and the input optical signal using the following mathematical formula 1.

[0079]

Equation

[0080] Here, Q 1 ~Q 4 are the respective charge amounts of the four electrical signals. Q 1 is the charge amount of the electrical signal corresponding to the reference signal having the same phase as the output optical signal. Q 2 is the charge amount of the electrical signal corresponding to the reference signal having a phase 180 degrees later than the output optical signal. Q 3 is the charge amount of the electrical signal corresponding to the reference signal having a phase 90 degrees later than the output optical signal. Q 4 is the charge amount of the electrical signal corresponding to the reference signal having a phase 270 degrees later than the output optical signal.

[0081] As a result, the depth information generation unit 30 can calculate the distance between the object and the camera device 1 using the phase difference between the output optical signal and the input optical signal. At this time, the depth information generation unit 30 can calculate the distance d between the object and the camera device 1 using the following mathematical formula 2.

[0082]

Equation

[0083] Here, c is the speed of light, and f is the frequency of the output light.

[0084] The control unit 40 controls the driving of the light output unit 10, the light input unit 20, and the depth information generation unit 30. The depth information generation unit 30 and the control unit 40 may be realized in the form of a PCB (printed circuit board) 50. Also, the depth information generation unit 30 and the control unit 40 may be realized in the form of other configurations. Alternatively, the control unit 40 may be included in the terminal where the camera device 1 according to the embodiment of the present invention is disposed. For example, the control unit 40 may be realized in the form of an application processor (AP) of a smartphone on which the camera device 1 according to the embodiment of the present invention is mounted.

[0085] According to the embodiment of the present invention, the light output unit outputs an output optical signal having polarization components that are divided, thereby maximizing the number of spots per unit area irradiated on the object, that is, the target surface, and minimizing the interference between the spots.

[0086] FIG. 4 shows the light output unit included in the camera device according to an embodiment of the present invention, and FIG. 5 shows the spot image on the target surface irradiated by the light output unit according to an embodiment of the present invention. Here, for the content related to the light output unit, all or part of the content related to the light output unit described in FIGS. 1 to 3 can be referred to. For the content that is the same as the content described in FIGS. 1 to 3, duplicate explanations are omitted.

[0087] Referring to FIG. 4, the optical output unit 400 includes a light source 410, a collimation lens 420, and a beam splitter 430.

[0088] Here, the light source 410 generates light. The light generated by the light source 410 may be infrared light with a wavelength of 770 to 3000 nm. For example, a light emitting diode (LED) can be used as the light source 410, and a plurality of light emitting diodes can be arranged in a certain pattern. Alternatively, the light source 410 may include an organic light emitting diode (OLED) or a laser diode (LD). Alternatively, the light source 410 may be an edge emitting laser (EEL). Alternatively, the light source 410 may be a vertical cavity surface emitting laser (VCSEL). The VCSEL is one of the laser diodes that converts an electrical signal into an optical signal and can output a wavelength of about 800 to 1000 nm, for example, a wavelength of about 850 nm or about 940 nm.

[0089] Here, the light source 410 can output a point illumination pattern. For example, when the light source 410 is a VCSEL, the light source 410 can easily control the spot size, position, density, and light amount within the point illumination pattern. The point illumination pattern means a spot array separated at regular intervals within a predetermined area and may be used interchangeably with a spot illumination pattern or a point light source pattern. Here, the point illumination pattern may mean a pattern in which light is locally concentrated in space, that is, a pattern in which light does not spread continuously in space but is locally concentrated. In the case of the point illumination pattern, since the light is locally concentrated, each spot has a large amount of light. This has the advantage that high-precision depth information can be obtained even when the distance from the object is far.

[0090] The collimation lens 420 is disposed on the light source 410 and collimates the light generated by the light source 410 and then output from the light source 410. The collimation lens 420 may be disposed on the optical path of the light output from the light source 410, or may be a part of the lens assembly 110 of the light output unit 10 described with reference to FIGS. 1 to 3.

[0091] The beam splitter 430 splits the light collimated by the collimation lens 420 after being output by the light source 410 into a first polarization component and a second polarization component. Here, one of the first polarization component and the second polarization component may be a P-polarized component (P-polarized), and the other may be an S-polarized component (S-polarized). The beam splitter 430 can split light into a P-polarized component and an S-polarized component using a birefringent crystal. The P-polarized component and the S-polarized component may be linearly polarized perpendicular to each other.

[0092] According to an embodiment of the present invention, the first polarization component and the second polarization component split by the beam splitter 430 are irradiated so as to be distinguishable from each other on an object, that is, on a target surface.

[0093] For this purpose, the light output unit 400 may further include a mirror 440.

[0094] The optical path of at least one of the first polarization component and the second polarization component split by the beam splitter 430 may be irradiated toward an object, that is, a target surface after being reflected by the mirror 440. In FIG. 4, after the light is split into the first polarization component and the second polarization component by the beam splitter 430, one of the first polarization component and the second polarization component is shown to go toward the object, and the other goes toward the object after being reflected by the mirror, but the present invention is not limited thereto. The number and position of the mirrors may be variously deformed according to the positions of the light source 410 and the beam splitter 430, etc.

[0095] Referring to FIG. 5, the first polarization component (e.g., P polarization component) and the second polarization component (e.g., S polarization component) may be simultaneously irradiated onto the object. That is, the first polarization component may be irradiated onto the object in a first spot array pattern, and the second polarization component may be irradiated onto the object in a second spot array pattern. The first spot array for the first polarization component (e.g., P polarization component) in FIG. 5(a) and the second spot array for the second polarization component (e.g., S polarization component) in FIG. 5(b) may be irradiated onto the object so as to be distinguishable from each other as shown in FIG. 5(c). That is, the first polarization component and the second polarization component may be simultaneously irradiated onto the object as shown in FIG. 5(c). Here, being simultaneously irradiated may mean that the first polarization component and the second polarization component reach the object at the same time. Alternatively, being simultaneously irradiated may mean that at least a part of the time regions in which the first polarization component and the second polarization component are irradiated onto the object overlaps. For example, the first polarization component reaches the object earlier than the second polarization component, but the second polarization component reaches the object while the first polarization component is being irradiated onto the object, or the second polarization component reaches the object earlier than the first polarization component, but the second polarization component reaches the object while the first polarization component is being irradiated onto the object. Referring to FIG. 5(c), the first spot array for the first polarization component and the second spot array for the second polarization component may be arranged in alignment with a predetermined interval on the same target surface. That is, the first spot array for the first polarization component may be arranged separated from the second spot array between the second spot arrays. Also, the second spot array for the second polarization component may be arranged separated from the first spot array between the first spot arrays. Thereby, the number of spots per unit area, that is, the density of the spots can be maximized, and thereby, the resolution of the depth information extraction can be increased.Also, referring to FIG. 5(c), since the boundaries between the first spot array for the first polarization component and the second spot array for the second polarization component are clearly distinguishable from each other, interference between different polarization components can be minimized, thereby enhancing the accuracy of depth information extraction.

[0096] According to an embodiment of the present invention, the mirror 440 can be used to align the first spot array for the first polarization component and the second spot array for the second polarization component. That is, the light output unit 400 can be pre-aligned using the mirror 440 such that the second spot array for the second polarization component is separated from each other at a predetermined interval between the first spot arrays for the first polarization component. That is, the light output unit 400 can be pre-calibrated or aligned using the mirror 440 such that the second spot arrays for the second polarization component do not overlap with each other but are as close as possible between the first spot arrays for the first polarization component.

[0097] FIG. 6 shows a light output unit included in a camera device according to another embodiment of the present invention. Duplicate descriptions of the same content described in FIGS. 1 to 5 are omitted.

[0098] Referring to FIG. 6, the light output unit 400 includes a light source 410, a collimation lens 420, a beam splitter 430, a mirror 440, a first optical element 450, and a second optical element 460.

[0099] The descriptions of the light source 410, the collimation lens 420, the beam splitter 430, and the mirror 440 are the same as those described in FIGS. 4 and 5, and thus duplicate descriptions are omitted for convenience of explanation.

[0100] According to an embodiment of the present invention, the first optical element 450 is disposed on the path irradiated with the first polarization component split by the beam splitter 430, and diffuses the first polarization component. Further, the second optical element 460 is disposed on the path irradiated with the second polarization component split by the beam splitter 430, and diffuses the second polarization component. For example, the first optical element 450 may be a diffractive optical element (DOE) that emits and outputs an n-fold spot array of the first polarization component, and the second optical element 460 may be a diffractive optical element (DOE) that emits and outputs an n-fold spot array of the second polarization component.

[0101] Although the first optical element 450 and the second optical element 460 are illustrated as separate configurations separated from each other, the present invention is not limited thereto. That is, one optical element may be disposed on the path irradiated with the first polarization component and the path irradiated with the second polarization component, and may simultaneously diffuse the first polarization component and the second polarization component.

[0102] When the camera device according to the embodiment of the present invention further includes the first optical element 450 and the second optical element 460, the density of the spots irradiated on the object can be increased without increasing the power consumption of the light source, so that the resolution of depth information extraction can be increased.

[0103] FIG. 7 shows the light output unit included in the camera device according to another embodiment of the present invention, and FIG. 8 shows the principle of the phase retardation member according to an embodiment of the present invention. Duplicate descriptions of the same content as that described in FIGS. 1 to 6 are omitted.

[0104] Referring to FIG. 7, the light output unit 400 includes a light source 410, a collimation lens 420, a beam splitter 430, a mirror 440, a first optical element 450, a second optical element 460, a first phase retardation member 470, and a second phase retardation member 480.

[0105] The descriptions of the light source 410, the collimation lens 420, the beam splitter 430, the mirror 440, the first optical element 450, and the second optical element 460 are the same as those described in FIGS. 4 to 6, and thus redundant descriptions are omitted for the sake of convenience of explanation.

[0106] According to an embodiment of the present invention, the first phase retardation member 470 retards the phase of the first polarization component, the second phase retardation member 480 retards the phase of the second polarization component, and the first polarization component retarded by the first phase retardation member 470 and the second polarization component retarded by the second phase retardation member 480 may be irradiated onto the object so as to be distinguishable from each other. The first phase retardation member 470 and the second phase retardation member 480 are shown to be disposed between the beam splitter 430 and the first optical element 450 and the second optical element 460, respectively, but are not limited thereto.

[0107] Depending on the surface material of the object, the polarization direction of the light reflected from the object may be different from the polarization direction of the light incident on the object. As a result, after the light of the first polarization component is reflected from the object, it can have a part of the characteristics of the second polarization component, and after the light of the second polarization component is reflected from the object, it can also have a part of the characteristics of the first polarization component. As a result, the reliability of the input optical signal input to the light input unit after being reflected from the object may decrease. According to an embodiment of the present invention, the first polarization signal and the second polarization signal are respectively retarded in phase by the first phase retardation member 470 and the second phase retardation member 480, thereby making the distinction between the first polarization signal and the second polarization signal clearer.

[0108] The polarization of light is the sum of the vector directions of the electric field and the magnetic field, and the phase difference between the electric field and the magnetic field, that is, the vector direction can be changed by the phase delay, and thereby the characteristics of the polarization can be changed. Referring to FIG. 8(a), when the orthogonal Ex and Ey propagate in the same direction, when the phases are the same, it is linearly polarized. Referring to FIG. 8(b), when the orthogonal Ex and Ey propagate in the same direction, when the phase difference is 90 degrees, it is circularly polarized. Referring to FIG. 8(c), when the orthogonal Ex and Ey propagate in the same direction, in the case of an arbitrary phase difference, it is elliptically polarized.

[0109] For example, when the light that has passed through the X-direction vertical polarization filter (hereinafter referred to as X-polarized light) passes through a quarter-wave retardation member with a phase difference of 90 degrees, it is circularly polarized clockwise. When the light that is circularly polarized clockwise passes through the quarter-wave retardation member again, it is Y-polarized. On the other hand, when Y-polarized light passes through the quarter-wave retardation member, it is circularly polarized counterclockwise. When the light that is circularly polarized counterclockwise passes through the quarter-wave retardation member again, it is X-polarized.

[0110] According to an embodiment of the present invention using such a principle, when one of the first polarization component and the second polarization component is a P-polarization component and the other is an S-polarization component, the first polarization component may be circularly polarized in a first direction by the first phase retardation member 470, and the second polarization component may be circularly polarized in a second direction different from the first direction by the second phase retardation member 480. The first direction may be clockwise, and the second direction may be counterclockwise. For example, the first polarization component may be circularly polarized clockwise, and the second polarization component perpendicular to the first polarization component may be circularly polarized counterclockwise.

[0111] In this way, when the first polarization component is reflected from the object after being circularly polarized in the first direction and the second polarization component is reflected from the object after being circularly polarized in the second direction, the interference between the first polarization component and the second polarization component after reflection can be reduced, so that the reliability of depth information extraction can be improved.

[0112] For this purpose, the first phase delay member 470 and the second phase delay member 480 may each be a quarter-wave plate, and may delay the phase of the first polarization component and the second polarization component by 90 degrees. When the first phase delay member 470 and the second phase delay member 480 are each a quarter-wave plate, the first polarization component incident on the first phase delay member 470 may be circularly polarized in the first direction, for example, clockwise, and the second polarization component incident on the second phase delay member 480 and perpendicular to the first polarization component may be circularly polarized in the second direction, for example, counterclockwise.

[0113] FIG. 9 illustrates the operation in the light input unit of the camera device according to an embodiment of the present invention.

[0114] Referring to FIG. 9, the light input unit 20 can receive the first polarization component input after being reflected from the object in the first time region T1, and can receive the second polarization component input after being reflected from the object in the second time region T2 that does not overlap with the first time region T1. The depth information generation unit 30 can generate the depth information of the object by combining the first polarization component and the second polarization component. That is, the depth information generation unit 30 can receive different polarization components in different time regions and can distinguish them as different components. Further, by combining the first polarization component and the second polarization component received in different time regions to generate the depth information of the object, the accuracy of depth information extraction can be improved.

[0115] Here, the units of the first time region T1 and the second time region T2 may be frames. For example, the optical input unit 20 may receive the first polarization component in odd-numbered frames and receive the second polarization component in even-numbered frames. For this purpose, the optical input unit 20 includes a first polarization filter (not shown) that selectively passes the first polarization component and a second polarization filter (not shown) that selectively passes the second polarization component. The first polarization filter and the second polarization filter may be driven in sequence in synchronization with the first time region T1 and the second time region T2. According to this, since the optical input unit can receive the first polarization component and the second polarization component separately, interference between the first polarization component and the second polarization component can also be reduced in the optical input unit, and the accuracy of depth information extraction can be improved.

[0116] FIG. 10 is a graph for explaining the effects according to an embodiment of the present invention.

[0117] FIG. 10(a) is a graph simulating pixel data according to the number of pixels in a comparative example in which an output optical signal is output without being divided into a first polarization component and a second polarization component. FIG. 10(b) is a graph simulating pixel data according to the number of pixels in an embodiment of the present invention in which an output optical signal is output after being divided into a first polarization component and a second polarization component. Here, the number of pixels may mean the position of a spot, and the pixel data may mean the brightness of a spot.

[0118] Referring to FIG. 10(a), since the difference between the peaks and valleys of the pixel data is not large, interference between adjacent spots may occur, and thereby the accuracy of depth information extraction may be reduced.

[0119] On the contrary, referring to FIG. 10(b), it can be seen that the distinction between the peaks and valleys of the pixel data of the first polarization component is clear, and the distinction between the peaks and valleys of the pixel data of the second polarization component is clear. According to this, since the distinction between the spots in the spot array becomes clear, interference between the spots can be minimized, and the accuracy of depth information extraction can be improved.

[0120] In the above description, the explanation has been centered around a camera device that extracts depth information using the ToF method. However, the embodiments of the present invention are not limited to this. The camera device according to the embodiments of the present invention may also mean a camera device that extracts depth information using the structured light method.

[0121] According to the structured light method, an object is irradiated with IR (Infrared) structured light of a predetermined pattern that is distinguishable from ambient illumination, and the distance is calculated by receiving the optical signal reflected from the object and analyzing the distortion. The method of projecting IR structured light onto an object has relatively high accuracy at short distances compared to other methods. However, since the accuracy significantly decreases as the distance increases, it has the limitation of a short drivable distance.

[0122] Referring again to FIGS. 1 and 2, the light output unit 10 irradiates an object after generating an output optical signal. Hereinafter, for the sake of convenience of explanation, duplicate explanations for the same content described in FIGS. 1 and 2 will be omitted.

[0123] At this time, the light output unit 10 can output an optical signal of a predetermined pattern. FIG. 11 is an example of an optical signal of a predetermined pattern. Referring to FIG. 11, the optical signal of a predetermined pattern may be composed of a plurality of points and may also be referred to as structured light. Here, the predetermined pattern may be a unique pattern or may be generated by a pre-designed algorithm. The optical signal of a predetermined pattern may be an IR (Infrared) optical signal. As described above, the light output unit 10 may include a light source 100 and a lens assembly 110. When the light source 100 includes a VCSEL, one VCSEL may have a plurality of emitters, for example, hundreds of emitters, and a pattern composed of points by each emitter may be output. That is, structured light having a predetermined pattern may be output by hundreds of emitters. The light source 100 can repeat blinking (on / off) at regular time intervals, and the regular time interval may be the frequency of the output optical signal.

[0124] The image sensor 140 can receive an input optical signal according to the blinking period of the light source 100. The image sensor 140 may be configured with a structure in which a plurality of pixels are arranged in a grid pattern. The image sensor 140 may be a CMOS (Complementary Metal Oxide Semiconductor) image sensor or a CCD (Charge Coupled Device) image sensor.

[0125] The light input unit 20 may be arranged side by side with the light output unit 10. The light input unit 20 may be arranged adjacent to the light output unit 10. The light input unit 20 may be arranged in the same direction as the light output unit 10.

[0126] The depth information generation unit 30 can generate depth information of an object using the input optical signal input to the light input unit 20. According to an embodiment of the present invention, the depth information generation unit 30 can generate depth information of an object using the disparity of the optical signal.

[0127] FIG. 12 is a diagram for explaining the principle of generating depth information using structured light. As described above, in this specification, structured light means an optical signal of a predetermined pattern composed of a plurality of points. Referring to FIG. 12, the object distance (h') between the camera device 1 and the object can vary depending on the disparity (Δx) of the points forming the structured light. That is, according to the structured light method, depth information can be extracted according to the degree of disparity caused by the distance change. Accordingly, the accuracy of the disparity can affect the accuracy of the depth information.

[0128] More specifically, the extraction of depth information using structured light can be performed by the following mathematical formula.

[0129]

Equation

[0130]

Number

[0131]

Number

[0132] Here, h is the reference distance, h' is the object distance, b is the length of the baseline, and Δx is the disparity.

[0133] Referring to Equation 3 to Equation 5, it can be seen that the length of the baseline (b) affects the disparity, and the disparity per unit length of the object distance (h') increases as the FOV (field of view) becomes smaller and the baseline becomes larger. When the size of the object is smaller than half of the baseline, the points within a predetermined pattern can overtake the adjacent points due to the disparity, and the disparity can decrease as the object distance increases. Therefore, in order to calculate accurate depth information, it is necessary to extract the disparity based on the center of the points.

[0134] The performance of depth information extraction according to the structured light method can vary depending on the measurement accuracy level of the center of the points and the measurement resolution of the disparity.

[0135] Figure 13 is a graph for explaining the change in disparity due to the difference between the reference distance and the object distance. Here, the reference distance is set to 300 nm as an example.

[0136] Referring to Fig. 13, it can be seen that the rate of change of disparity decreases as the object distance increases. For example, when the object distance is 900 mm or less, the slope of the graph, that is, the change in disparity with respect to the change in distance is large. However, when the object distance exceeds 900 mm, it can be seen that the slope of the graph becomes significantly smaller. In particular, it can be seen that the slope of the graph becomes smaller as the object distance increases.

[0137] From this, it can be seen that the measurement accuracy of disparity decreases as the distance difference between the reference distance and the object increases.

[0138] In order to solve such problems, the number of pixels of the image sensor can be increased.

[0139] Fig. 14 shows the disparity measurement performance according to the number of pixels of the image sensor.

[0140] Referring to Fig. 14, Figs. 14(a) and 14(b) show the pixel values of an image sensor having 9*9 pixels, and Figs. 14(c) and 14(d) show the results of showing the pixel values using an image sensor having 3*3 pixels for the same object as Figs. 14(a) and 14(b), respectively.

[0141] Referring to Figs. 14(a) and 14(b), when using a high-pixel image sensor having 9*9 pixels, the values in Figs. 14(a) and 14(b) are distinguishable. However, referring to Figs. 14(c) and 14(d), when using a low-pixel image sensor having 3*3 pixels, it can be seen that the values in Figs. 14(c) and 14(d) are not distinguishable.

[0142] However, when using a high-pixel image sensor, there is a problem that the power consumption and the amount of calculation of the entire camera device increase, and the cost of the camera device increases significantly.

[0143] In an embodiment of the present invention, an attempt is made to improve the measurement accuracy of disparity at a long distance without using a high-pixel image sensor.

[0144] FIG. 15 is a block diagram of a camera device according to an embodiment of the present invention, and FIG. 16 is a conceptual diagram of the camera device according to an embodiment of the present invention.

[0145] Referring to FIGS. 15 and 16, a camera device 700 according to an embodiment of the present invention includes a light output unit 710, a light input unit 720, a depth information generation unit 730, and a control unit 740. The light output unit 710, the light input unit 720, the depth information generation unit 730, and the control unit 740 are respectively configured to correspond to the light output unit 10, the light input unit 20, the depth information generation unit 30, and the control unit 40 described with reference to FIGS. 1 and 2. For the sake of convenience of explanation, duplicate explanations of the same content as that of the camera device 1 described with reference to FIGS. 1 and 2 are omitted.

[0146] The light output unit 710 irradiates an object after generating an output optical signal. At this time, the light output unit 710 can output an optical signal of a predetermined pattern.

[0147] According to an embodiment of the present invention, the light output unit 710 includes a first optical system 712 that irradiates an object with an optical signal of a first field of illumination (FOI), and a second optical system 714 that irradiates an object with an optical signal of a second field of view smaller than the first field of view.

[0148] More specifically, as shown in FIG. 16, when the first optical system 712 of the light output unit 710 is driven, the first optical system 712 irradiates an object with an optical signal of a predetermined pattern composed of a plurality of points at the first field of view. Further, when the second optical system 714 of the light output unit 710 is driven, the second optical system 714 irradiates an object with an optical signal of a predetermined pattern composed of a plurality of points at a second field of view smaller than the first field of view.

[0149] According to this, when the first optical system 712 and the second optical system 714 output optical signals of the same pattern, the dot density of the optical signal output through the first optical system 712 may be lower than the dot density of the optical signal output through the second optical system 714 for the same distance. That is, when the first optical system 712 and the second optical system 714 output optical signals of the same pattern, the distance that the optical signal output through the second optical system 714 reaches for the same dot density may be longer than the distance that the optical signal output through the first optical system 712 reaches. Here, the dot density may mean the number of dots per unit area.

[0150] Thus, the first optical system 712 that irradiates the object with the optical signal of the first angle of view is used for generating depth information at a short distance, and the second optical system 714 that irradiates the object with the optical signal of the second angle of view smaller than the first angle of view may be used for generating depth information at a longer distance than the distance measured by the first optical system 712. For example, the first optical system 712 may be used for generating depth information at an object distance of 900 mm or less, and the second optical system 714 may be used for generating depth information at an object distance exceeding 900 mm.

[0151] For this purpose, the first optical system 712 may include a first light source 800 and a first diffractive optical element (DOE) 802 that diffuses the light output by the first light source 800 at a first angular field of view. The second optical system 714 may include a second light source 810 and a second diffractive optical element 812 that diffuses the light output by the second light source 810 at a second angular field of view. At this time, the first light source 800 and the second light source 810 output light of the same pattern, and the light output by the first light source 800 is radiated n*n times by the first diffractive optical element 802 and irradiates the object, and the light output by the second light source 810 may be radiated n*n times by the second diffractive optical element 812 and irradiate the object. At this time, n may be an integer of 2 or more. For this purpose, the first diffractive optical element 802 and the second diffractive optical element 812 have the same shape, but may be designed such that the angle at which the light passing through the first diffractive optical element 802 spreads is larger than the angle at which the light passing through the second diffractive optical element 812 spreads.

[0152] According to this, the pattern shape of the optical signal irradiated to the object through the first optical system 712 and the pattern shape of the optical signal irradiated to the object through the second optical system 714 may be the same. When the pattern shape of the optical signal irradiated to the object through the first optical system 712 and the pattern shape of the optical signal irradiated to the object through the second optical system 714 are the same, the depth information generation unit 730 can apply the same operation to the optical signal input after being irradiated to the object through the first optical system 712 and the optical signal input after being irradiated to the object through the second optical system 714. Therefore, the computational complexity of the depth information generation unit 730 can be reduced.

[0153] On the other hand, according to an embodiment of the present invention, the first optical system 712 may further include a first collimator lens 804, and the second optical system 714 may further include a second collimator lens 814. The collimator lens means a lens that condenses the light output from the light source.

[0154] The first collimator lens 804 is disposed between the first light source 800 and the first diffractive optical element 802, and can collect the light output by the first light source 800 onto the first diffractive optical element 802. The second collimator lens 814 is disposed between the second light source 810 and the second diffractive optical element 812, and can collect the light output by the second light source 810 onto the second diffractive optical element 812.

[0155] Here, although the description is made assuming that the first optical system 712 includes the first light source 800 and the second optical system 714 includes the second light source 810, the embodiments of the present invention are not limited thereto. Although not shown, the first optical system 712 and the second optical system 714 may include a common light source, and the light output from the light source may be aligned so as to be directed to the first diffractive optical element 802 or the second diffractive optical element 812 by alignment or movement of the first collimator lens 804 and the second collimator lens 814.

[0156] The first diffractive optical element 802, the first collimator lens 804, the second diffractive optical element 812, and the second collimator lens 814 described here may be part of the lens assembly 110 of the light output unit 10 described with reference to FIGS. 1 and 2.

[0157] According to an embodiment of the present invention, the light input unit 720 includes a zoom optical system 722 and an image sensor 724 that are driven at a first magnification or a second magnification higher than the first magnification. Referring to FIG. 8, an IR band-pass filter 726 that passes IR light may be further disposed between the zoom optical system 722 and the image sensor 724.

[0158] FIG. 17 is a block diagram of a zoom optical system according to an embodiment of the present invention. Referring to FIG. 17, the zoom optical system 722 may include a zoom lens 900 and an actuator 902 that drives the zoom lens 900 at a first magnification or a second magnification higher than the first magnification. The zoom lens 900 includes one or more lenses and can be moved by the actuator 902. The zoom lens 900 includes a plurality of lenses, and a part of the plurality of lenses may be a fixed group and another part may be a moving group. By moving the zoom lens 900, the distance between the zoom lens 900 and the image sensor 724 changes, and thus the magnification can be adjusted.

[0159] For example, the first magnification may be 1× and the second magnification may be 3×, but is not limited thereto, and the second magnification may be at least one of 2×, 3×, 4×, 5×, 6×, and 7×. Alternatively, the zoom optical system 722 may be a continuous zoom optical system that can be adjusted to any value of magnification from 1× to 7×. Alternatively, the zoom optical system 722 may include a folded lens. According to this, the volume occupied by the zoom optical system 722 in the light input unit 720 can be minimized.

[0160] As described above, when the light input unit 720 includes the zoom optical system 722, the optical signal received by the light input unit 720 can be enlarged. According to this, since the plurality of points forming the optical signal and the distances between them can be enlarged, the position of the center of the points and the disparity can be measured more accurately.

[0161] According to an embodiment of the present invention, the control unit 740 interlocks the light output unit 710 and the light input unit 720.

[0162] As described above, the second optical system 714 having an angle of view narrower than that of the first optical system 712 may be applied to generate depth information at a longer distance than the measurement distance of the first optical system 712. However, as described with reference to FIG. 13, the rate of change of disparity decreases as the object distance increases. As described with reference to FIG. 14, in order to solve such a problem, the number of pixels of the image sensor may be increased, but this may increase the power consumption, calculation complexity, and cost of the camera device.

[0163] However, according to an embodiment of the present invention, when the control unit 740 interlocks the light output unit 710 and the light input unit 720, it is possible to obtain a camera device that can generate accurate depth information not only at a short distance but also at a medium to long distance without increasing the number of pixels of the image sensor.

[0164] That is, according to an embodiment of the present invention, when the first optical system 712 of the light output unit 710 is driven, the control unit 740 controls the zoom optical system 722 to be driven at the first magnification. When the second optical system 714 of the light output unit 710 is driven, the control unit 740 controls the zoom optical system 722 to be driven at a second magnification higher than the first magnification. For example, when the first light source 800 of the first optical system 712 is turned on, the control unit 740 controls the zoom optical system 722 to be driven at the first magnification. When the second light source 810 of the second optical system 714 is turned on, the control unit 740 can control the zoom optical system 722 to be driven at the second magnification. In this way, when the zoom optical system 722 is driven at the second magnification during the driving of the second optical system 714, the points of the optical signal input to the light input unit 720 and the distance between them are spread wider than when the optical system 722 is driven at the first magnification. Therefore, the center of the points and the disparity can be accurately measured.

[0165] According to an embodiment of the present invention, the control unit 740 can control so that one of the first optical system 712 and the second optical system 714 is selectively driven. For example, the control unit 740 may control so that the first optical system 712 is driven, and in conjunction with this, control so that the zoom optical system 722 is driven at a first magnification. Alternatively, the control unit 740 may control so that the second optical system 714 is driven, and in conjunction with this, control so that the zoom optical system 722 is driven at a second magnification.

[0166] According to an embodiment of the present invention, it may be set so that the first optical system 712 is preferentially driven by an initial setting, and the control unit 740 may control so as to be driven to change from the first optical system 712 to the second optical system 714. Alternatively, it may be set so that the second optical system 714 is preferentially driven by an initial setting, and the control unit 740 may control so as to be driven to change from the second optical system 714 to the first optical system 712. Here, the control unit 740 may control the change drive according to information input through the user interface unit or information input from an external device. Alternatively, the control unit 740 may control the change drive according to the depth information generated by the depth information generation unit 730.

[0167] Hereinafter, a method for generating depth information of a camera device according to an embodiment of the present invention will be described more specifically.

[0168] FIG. 18 is a flowchart showing a method for generating depth information of a camera device according to an embodiment of the present invention, and FIG. 19 is a flowchart showing a step in which a control unit interlocks an optical output unit and an optical input unit in the depth information generation method of FIG. 18.

[0169] Referring to FIG. 18, the optical output unit 710 irradiates an object with an optical signal of a predetermined pattern composed of a plurality of points (S1000). Here, the optical output unit 710 irradiates the object with an optical signal having a first angle of view, or irradiates the object with an optical signal having a second angle of view smaller than the first angle of view.

[0170] Next, the control unit 740 interlocks the optical output unit 710 and the optical input unit 720 (S1010). For example, referring to FIG. 19, when the optical output unit 710 irradiates an object with an optical signal having a first field angle (S1100), the control unit 740 controls the zoom lens of the optical input unit 720 to be driven at a first magnification (S1110). When the optical output unit 710 does not irradiate the object with the optical signal having the first field angle but irradiates the object with the optical signal having the second field angle (S1120), the control unit 740 controls the zoom lens of the optical input unit 720 to be driven at a second magnification higher than the first magnification (S1130).

[0171] Next, referring again to FIG. 18, the optical input unit 720 receives the optical signal input after being reflected from the object (S1020), and the depth information generation unit 730 generates the depth information of the object using the disparity of the optical signal input to the optical input unit 720 (S1030).

[0172] On the other hand, according to an embodiment of the present invention, the control unit 740 can selectively control whether the optical output unit 710 irradiates an object with an optical signal having a first field angle or an optical signal having a second field angle smaller than the first field angle. For example, the control unit 740 may selectively control whether the optical output unit 710 irradiates an object with an optical signal having a first field angle or an optical signal having a second field angle according to the information input through the user interface or the information input from an external device. Alternatively, the control unit 740 may selectively control whether the optical output unit 710 irradiates an object with an optical signal having a first field angle or an optical signal having a second field angle according to the depth information generated in the step of generating the depth information of the object (S1030).

[0173] FIG. 20 is a flowchart showing a control method of a camera device according to an embodiment of the present invention.

[0174] Referring to FIG. 20, the light output unit 710 irradiates an object with an optical signal having a first field angle (S1200), the light input unit 720 receives the optical signal at a first magnification (S1210), and the depth information generation unit 730 generates depth information using the received optical signal (S1220).

[0175] At this time, when the generated depth information is equal to or less than a preset distance (S1230), the control unit 740 can control the light output unit 710 to irradiate the object with an optical signal having a first field angle (S1200), the light input unit 720 to receive the optical signal at a first magnification (S1210), and the depth information generation unit 730 to generate depth information using the received optical signal (S1220). Here, the preset distance means the object distance and may be, for example, 900 mm.

[0176] On the contrary, when the generated depth information exceeds the preset distance, the control unit 740 can control the light output unit 710 to irradiate the object with an optical signal having a second field angle (S1240), the light input unit 720 to receive the optical signal at a second magnification (S1250), and the depth information generation unit 730 to generate depth information using the received optical signal (S1220).

[0177] According to this, in a state where the first optical system 712 of the light output unit 710 is initially set to be driven, when the object is at a medium distance or more, for example, a distance exceeding 900 mm, the field angle of the light output unit 710 and the magnification of the light input unit 720 can be adaptively adjusted.

[0178] Also, in a state where the second optical system 714 of the light output unit 710 is driven, when the object is at a short distance, for example, a distance of 900 mm or less, the field angle of the light output unit 710 and the magnification of the light input unit 720 can be adaptively adjusted for short distances.

[0179] According to this, without the user having to set it separately, it can be automatically converted from the short-distance mode to the long-distance mode or from the long-distance mode to the short-distance mode, so that depth information can be accurately and quickly extracted for a moving object.

[0180] FIG. 21 shows an example in which the disparity measurement performance is improved when the light input unit includes a zoom lens according to an embodiment of the present invention.

[0181] FIG. 21(a) is an image of the image sensor when the light input unit does not include a zoom lens, and FIG. 21(b) is an image of the image sensor when the light input unit includes a zoom lens according to an embodiment of the present invention.

[0182] Referring to FIG. 21(a), since some of the points overlap each other, it can be seen that it is difficult to accurately calculate the center and disparity of the points.

[0183] On the other hand, referring to FIG. 21(b), when the image is magnified 5 times using the zoom lens, the center and disparity of the points can be calculated more accurately.

[0184] Accordingly, according to an embodiment of the present invention, the problem that the sensitivity of disparity decreases as the distance increases can be solved, and the structured light type camera device can be used not only for generating depth information at short distances but also at medium and long distances.

[0185] In this specification, an example in which the zoom optical system is driven at a first magnification or a second magnification higher than the first magnification is mainly described, but it is not limited thereto. The zoom optical system may be driven at a magnification of 2 times or more. For example, the zoom optical system may be driven at a first magnification, a second magnification higher than the first magnification, or a third magnification higher than the second magnification. Alternatively, the zoom optical system may be a continuous zoom optical system in which the magnification continuously changes.

[0186] The camera device according to an embodiment of the present invention may mean a camera device mounted on an automobile for measuring the distance between the automobile and an object, but is not limited thereto. For example, the camera device according to an embodiment of the present invention may be a LIDAR (Light Detection and Ranging) camera.

[0187] As described above, the description has been centered on the embodiments, which are merely illustrative and do not limit the present invention. It will be understood by those of ordinary skill in the art to which the present invention pertains that various modifications and applications not exemplified above are possible without departing from the essential characteristics of the present embodiment. For example, each component specifically shown in the embodiment can be implemented with modifications. Also, differences regarding such modifications and applications should be construed as being included in the scope of the present invention defined by the appended claims.

Description of Reference Numerals

[0188] 1, 700: Camera device 10, 710: Light output unit 20, 720: Light input unit 30, 730: Depth information generation unit 40, 740: Control unit 100: Light source 400: Light output unit 410: Light source 420: Collimation lens 430: Beam splitter 440: Mirror 712: First optical system 714: Second optical system 722: Zoom optical system 724: Image sensor 726: IR band-pass filter 800: First light source 802: First diffractive optical element 804: First collimator lens 810: Second light source 812: Second diffractive optical element 814: Second collimator lens

Claims

1. A light output unit that generates an output optical signal and irradiates an object, a light input unit that receives an input optical signal input after being reflected from the object, a depth information generation unit that generates depth information of the object using the input optical signal input to the light input unit, and includes: The light output unit a light source that generates the output optical signal, a beam splitter that splits the output optical signal generated by the light source into a first polarization component and a second polarization component that are different from each other, and includes: The first polarization component and the second polarization component are irradiated onto the object so as to be distinguishable from each other, a camera device.

2. The light output unit a first phase delay member that phase-delays the first polarization component, a second phase delay member that phase-delays the second polarization component, and further includes: The first polarization component phase-delayed by the first phase delay member and the second polarization component phase-delayed by the second phase delay member are irradiated onto the object so as to be distinguishable from each other, the camera device according to claim 1.

3. One of the first polarization component and the second polarization component is a P polarization component, and the other is an S polarization component, The first polarization component is circularly polarized in a first direction by the first phase delay member, and the second polarization component is circularly polarized in a second direction different from the first direction by the second phase delay member, the camera device according to claim 2.

4. The first polarization component is irradiated onto the object in a first spot array shape, and the second polarization component is irradiated onto the object in the second spot array shape, The first spot array is arranged spaced apart from the second spot array between the second spot arrays, the camera device according to claim 1.

5. The first polarization component and the second polarization component are simultaneously irradiated onto the object, the camera device according to claim 1.

6. At least one of the first polarization component and the second polarization component split by the beam splitter is irradiated onto the object after being reflected by a mirror, the camera device according to claim 1.

7. a first optical element disposed on the path irradiated by the first polarization component and diffusing the first polarization component, and a second optical element disposed on the path irradiated by the second polarization component and diffusing the second polarization component, and further includes: The camera device according to claim 1, wherein at least one of the first optical element and the second optical element is a diffractive optical element (DOE).

8. The light input unit receives the first polarization component that is input after being reflected from the object in a first time region, and receives the second polarization component that is input after being reflected from the object in a second time region that does not overlap with the first time region. The depth information generation unit generates depth information of the object using the first polarization component and the second polarization component. The camera device according to claim 1.

9. The depth information generation unit generates the depth information using at least one of a phase difference and a time difference between the output optical signal and the input optical signal. The camera device according to claim 1.

10. The output optical signal is structured light having a predetermined pattern, and the depth information generation unit generates the depth information using the disparity of the structured light. The camera device according to claim 1.

Images