Distance measurement camera device

Abstract

A distance measuring camera device according to an embodiment of the present invention includes a light emitting unit and a light receiving unit including an image sensor, the light emitting unit including a light source including a light emitting element, and a diffusion member arranged on the light source and including a plurality of microlenses, the diffusion member including a first region and a second region, the first region being arranged to surround the second region, the second region being arranged so that its center overlaps with the light emitting unit in the optical axis direction, and the diameter of the microlenses located in the second region being smaller than the diameter of the microlenses located in the first region.

Description

Technical Field

[0001] The embodiment relates to a distance measurement camera device.

Background Art

[0002] Three-dimensional content is applied in various fields such as games, culture, education, manufacturing, and autonomous driving. To obtain three-dimensional content, depth information (Depth Map) is required. Depth information is information indicating the distance in space, and indicates the perspective information of other points with respect to a certain point in a two-dimensional video.

[0003] As a method for obtaining depth information, ToF (Time of Flight) has recently attracted attention. According to the ToF method, the distance to an object is calculated by measuring the flight time, that is, the time it takes for light to be emitted and reflected back. The biggest advantage of the ToF method is that it can quickly provide distance information for a three-dimensional space in real time. In addition, accurate distance information can be obtained without the user applying a separate algorithm or hardware correction. Also, accurate depth information can be obtained even when measuring a very close subject or a moving subject.

[0004] However, unlike a camera module that does not use a separate light source, a ToF camera has a structure that outputs light by a light source, so safety problems may occur. In particular, when light with a high light intensity irradiates a light-sensitive part of the body such as the eye, it can lead to serious injury. To prevent such accidents, ToF camera modules are manufactured in accordance with strict safety regulations. Therefore, a camera module that can solve such problems is required.

Summary of the Invention

Problems to be Solved by the Invention

[0005] The embodiment provides a ToF distance measurement camera device that provides a high level of safety.

[0006] The problems to be solved in the embodiments are not limited to this, and should also include the means for solving the problems described below and the objects and effects that can be grasped from the embodiments.

Means for Solving the Problems

[0007] The distance measurement camera device according to an embodiment of the present invention includes a light emitting unit and a light receiving unit including an image sensor. The light emitting unit includes a light source including a light emitting element and a diffusion member disposed on the light source and including a plurality of microlenses. The diffusion member includes a first region and a second region. The first region is disposed so as to surround the second region. The second region is disposed such that the center overlaps with the light emitting unit in the optical axis direction. The diameter of the microlens located in the second region is smaller than the diameter of the microlens located in the first region.

[0008] The second region includes a plurality of sub-regions. The plurality of sub-regions may include a first sub-region adjacent to the first region and including a microlens having a first diameter, and a second sub-region surrounded by the first sub-region and including a microlens having a second diameter smaller than the first diameter.

[0009] The first diameter may be the same as the diameter of the microlens disposed in the first region.

[0010] The plurality of sub-regions may further include a third sub-region including the center of the diffusion member, surrounded by the second sub-region, and in which a microlens having a third diameter smaller than the second diameter is disposed.

[0011] The area of the second region may increase discretely as the separation distance between the diffusion member and the light source increases.

[0012] The minimum area of the second region can be set using the following mathematical formula.

[0013] TIFF0007714546000001.tif17144

[0014] Here, E means the horizontal or vertical length of the second region, D means the separation distance between the diffusion member and the light source, θ means the divergence angle of the light source, and t may mean the maximum separation distance between the centers of the light-emitting elements arranged in the same row or column among the plurality of light-emitting elements included in the light source.

[0015] The light source is input with a current between the magnitude of the first current and the magnitude of the second current, and the divergence angle of the light source can be set based on the output of the light output by the light source when the current of the magnitude of the second current is input.

[0016] The divergence angle of the light source may be an angle at which the light intensity is 1 / e 2 times the maximum light intensity of the light source is output.

[0017] The diameter of the microlens located in the second region may be 150 μm or less.

[0018] The distance measurement camera device includes a light-emitting unit and a light-receiving unit including an image sensor. The light-emitting unit includes a light source including light-emitting elements and a diffusion member disposed on the light source and including a plurality of microlenses. The diffusion member includes a first region and a second region. The first region is disposed so as to surround the second region. The second region is disposed such that the center overlaps with the light-emitting unit in the optical axis direction. The diameter of the microlens located in the first region is 150 μm or less.

Advantages of the Invention

[0019] According to the embodiment, a ToF distance measurement camera device providing a high safety level can be implemented.

[0020] The various and beneficial merits and effects of the present invention are not limited to the above-described content, and will be more easily understood in the process of describing the specific embodiments of the present invention.

Brief Description of the Drawings

[0021]

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Mode for Carrying Out the Invention

[0022] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0023] However, the technical idea of the present invention is not limited to the specific embodiments described, but can be embodied in various different forms. Within the scope of the technical idea of the present invention, one or more of the components can be selectively combined, replaced, and used among the embodiments.

[0024] In addition, terms (including technical and scientific terms) used in the embodiments of the present invention, unless specifically defined and described otherwise, should be interpreted as having a meaning generally understood by those with ordinary knowledge in the technical field to which the present invention pertains. Terms that are generally used like pre-defined terms can be interpreted in consideration of their meaning in the context of the related technology.

[0025] Furthermore, 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.

[0026] In this specification, the singular form may include the plural form unless otherwise specifically stated in the text. When described as "at least one (or one or more) of A, B, and C", it can include one or more of all combinations formed by A, B, and C.

[0027] Also, when describing the components of the embodiments of the present invention, terms such as first, second, A, B, (a), (b), etc. can be used.

[0028] Such terms are only for distinguishing the components from other components and are not limited to the essence, order, or procedure of the components by those terms.

[0029] And when a component is described as being "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 another component between the component and the other component.

[0030] Also, when it is described that it is formed or arranged “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 additional components are formed or arranged between the two components. Moreover, when expressed as “above” or “below”, it may include the meaning not only in the upward direction but also in the downward direction with respect to one component.

[0031] FIG. 1 is a configuration diagram of a distance measurement camera device according to an embodiment of the present invention.

[0032] The distance measurement camera device 1000 according to an embodiment of the present invention may mean a camera or a camera device that extracts depth information using a ToF (Time of Flight) function. Therefore, the distance measurement camera device 1000 may be used interchangeably with a ToF distance measurement camera device, a ToF camera device, a ToF camera module, and a ToF camera.

[0033] Referring to FIG. 1, the distance measurement camera device 1000 according to an embodiment of the present invention may include a light emitting unit 100 and a light receiving unit 200.

[0034] The light emitting unit 100 may be a unit that outputs the generated optical signal to an object after generating the optical signal. For this purpose, the light emitting unit 100 may include a configuration capable of generating light together with a light emitting element and a configuration capable of modulating light. The optical signal may be 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.

[0035] Referring to FIG. 1, the light emitting unit 100 can include a light source 110 and a diffusing member 120. The light source 110 can generate light. The light source 110 can output light. The light source 110 can irradiate light. The light generated by the light source 110 can be infrared light with a wavelength of 770 to 3000 nm. Alternatively, the light generated by the light source 110 can be visible light with a wavelength of 380 to 770 nm. After receiving the light output from the light source 110, the diffusing member 120 can diffract the received light and output it. The diffusing member 120 can condense light and convert it into parallel light. The diffusing member 120 can be a Micro Lens Array (MLA).

[0036] The light receiving unit 200 can sense the light reflected by the object. The light receiving unit 200 can sense the optical signal reflected by the object. At this time, the sensed optical signal can be the one in which the optical signal output by the light emitting unit 100 is reflected by the object.

[0037] The light receiving unit 200 can include a lens assembly, a filter, and a sensor to sense the optical signal. The optical signal reflected from the object can pass through the lens assembly. The optical axis of the lens assembly can be aligned with the optical axis of the sensor. The filter can be disposed between the lens assembly and the sensor. The filter can be disposed on the optical path between the object and the sensor. The filter can filter light having a predetermined wavelength range. The filter can transmit a specific wavelength band of light. The filter can allow light of a specific wavelength to pass through. For example, the filter can allow light in the infrared band to pass through and block light outside the infrared band. The sensor can sense light. The sensor can receive the optical signal. The sensor can be an image sensor that senses the optical signal. The sensor can sense the optical signal and output it as an electrical signal. The sensor can sense light having a wavelength corresponding to the wavelength of the light output from the light emitting element. For example, the sensor can sense light in the infrared band.

[0038] The light-receiving part 200 and the light-emitting part 100 can be arranged in parallel. The light-receiving part 200 can be arranged next to the light-emitting part 100. The light-receiving part 200 can be arranged in the same direction as the light-emitting part 100.

[0039] Figure 2 is a schematic circuit diagram of the light-emitting part according to an embodiment of the present invention.

[0040] Referring to Figure 2, the light-emitting part 100 according to an embodiment of the present invention includes a light source 110 and a diffusion member 120.

[0041] According to an embodiment of the present invention, the light source 110 can include a plurality of light-emitting elements 112. Specifically, the light source 110 can be embodied in an array form in which a plurality of light-emitting elements 112 are arranged on a substrate 111 according to a predetermined rule. The substrate 111 includes a first surface and a second surface. A plurality of light apertures can be formed on the first surface of the substrate 111, and a plurality of diffusion members 120 can be arranged on the substrate 111 corresponding to the plurality of light apertures. The light source 110 outputs light through the light apertures, and the light can be output at a predetermined divergence angle. The plurality of light-emitting elements 112 can be vertical-cavity surface-emitting lasers (VCSELs).

[0042] The diffusion member 120 can be divided into a body part 121 and a plurality of microlens parts 122. Specifically, the diffusion member 120 can be in a shape in which a plurality of microlenses 122 are arranged on the body part 121 according to a predetermined rule. The diffusion member 120 can be integrally formed with the body part 121 and the plurality of microlenses 122. At this time, the body part 121 and the microlenses 122 can be formed of the same material as each other. The body part 121 can be in the shape of a plate.

[0043] The diffusion member 120 can be divided into a first surface for receiving light from the light source 110 and a second surface for outputting light. The first surface of the diffusion member 120 can include a horizontal surface or a curved surface, and a plurality of microlenses 122 can be arranged on the second surface of the diffusion member 120.

[0044] The plurality of microlenses 122 may have a predetermined diameter. The diameters of the plurality of microlenses 122 may be set such that the maximum value among the light beam concentration degrees of the plurality of microlenses does not exceed a predetermined value. Here, the light beam concentration degree can mean the ratio of the light beam incident on one microlens as compared with the total energy output from the light source 110.

[0045] According to an embodiment of the present invention, the diameters of the plurality of microlenses 122 are set such that the maximum value among the light beam concentration degrees of the plurality of microlenses does not exceed a predetermined value, and the diameters of the plurality of microlenses 122 can be designed to be the same as each other.

[0046] According to another embodiment of the present invention, the diffusion member 120 can be divided into a plurality of regions, and the diameters of the microlenses 122 arranged in some regions among the plurality of regions can be made smaller than the diameters of the microlenses 122 arranged in other regions. Specifically, the second surface of the diffusion member 120 can be divided into a first region 125 and a second region 126, and the second region 126 can be divided into a plurality of sub-regions. The first region 125 is arranged so as to surround the second region 126, the second region 126 can be arranged so as to overlap with the light emitting unit 100 in the optical axis direction, and the center of the second region 126 can be arranged so as to overlap with the center of the diffusion member 120. And the second region 126 may include a plurality of sub-regions. As an example, the plurality of sub-regions can include two or three sub-regions. At this time, the diameters of the microlenses 122 arranged in at least one of the plurality of sub-regions can be made smaller than the diameters of the microlenses 122 arranged in the first region 125.

[0047] FIG. 3 is a diagram for explaining the light beam concentration degree of the diffusion member according to an embodiment of the present invention.

[0048] FIG. 3 schematically shows the diffusion member 120, where each cell means a single microlens. FIG. 3 shows a form in which microlenses having a diameter of 300 μm are arranged in an 8×8 array. The shading shown in each cell indicates the ratio of the total energy output by the light source 110 that is concentrated on each microlens. In FIG. 3, it means that the microlenses arranged in the places where the hue of the shading is darker have higher concentrated energy.

[0049] Referring to FIG. 3, the ratio of microlenses where a light beam concentration degree of approximately 9% or more appears with respect to the total energy output by the light source is 4 / 64. The ratio of microlenses where a light beam concentration degree of approximately 0.5% or more and 9% or less appears with respect to the total energy output by the light source is about 45 / 64.

[0050] Even if a light beam concentration degree of approximately 9% or more appears with respect to the total energy output by the light source, when the microlens is normal, it diffracts and scatters light and outputs it, so the energy concentrated on the microlens is not directly transmitted to the subject. However, when the microlens is damaged, the energy concentrated on the microlens can be directly transmitted to the subject. If the subject is a person, it may even cause blindness. Therefore, it is necessary to disperse the energy concentrated on a single microlens to improve safety.

[0051] FIG. 4 is a diagram showing a diffusion member according to an embodiment of the present invention.

[0052] According to an embodiment of the present invention, the diameter of the plurality of microlenses of the diffusion member 120 can be designed such that the light flux concentration degree of each of the plurality of microlenses is dispersed. Specifically, according to an embodiment of the present invention, the diameter of the microlenses of the diffusion member 120 can be set such that the maximum value among the light flux concentration degrees of the plurality of microlenses does not exceed a predetermined value. For example, the diameter of the microlenses of the diffusion member 120 can be set such that the maximum value among the light flux concentration degrees of the plurality of microlenses does not exceed 2.5%. According to one embodiment, the plurality of microlenses can be designed to have a diameter of 150 μm or less. For example, the diffusion member 120 can be embodied as a microlens having a diameter of 100 μm or a microlens having a diameter of 50 μm. According to another embodiment, the plurality of microlenses can be designed to have a diameter of a value included in the range of -10% to 10% centered on 150 μm or less. For example, the diffusion member 120 can be designed to have a diameter of 135 μm or less or a diameter of 165 μm or less.

[0053] FIG. 4 shows a form in which microlenses having a diameter of 150 μm are arranged in a 16×16 array. Referring to FIG. 4, the ratio of microlenses in which a light flux concentration degree of approximately 0.5% or more and 9% or less appears with respect to the total energy output from the light source is about 60 / 256. In particular, it can be seen that there are no microlenses in which a light flux concentration degree of approximately 9% or more appears with respect to the total energy output from the light source. That is, even if some of the microlenses are damaged, since the ratio of the energy concentrated on one microlens is low, there is an advantage that the safety can be enhanced.

[0054] FIG. 5 is a diagram for explaining a diffusion member according to an embodiment of the present invention.

[0055] The smaller the diameter of the microlens, the smaller the energy concentrated on a single microlens and the higher the safety. However, in this case, the difficulty in the manufacturing process of the diffusion member 120 also increases accordingly. Therefore, the diffusion member 120 according to the embodiment of the present invention can solve the above problems by setting the diameters of the microlenses arranged in a plurality of mutually divided regions to be different.

[0056] The diffusion member 120 according to the embodiment of the present invention includes a first region 125 and a second region 126. The diameter of at least one of the microlenses 122 arranged in the second region 126 can be made smaller than the diameter of the microlenses 122 arranged in the first region 125.

[0057] The first region 125 and the second region 126 can be set to be different from each other according to the separation distance between the diffusion member 120 and the light source 110. According to the embodiment of the present invention, the diffusion member 120 can be arranged at a distance from the light source 110. The second region 126 can be set to be different from each other according to the separation distance between the diffusion member 120 and the light source 110. The area of the second region 126 can increase as the separation distance between the diffusion member 120 and the light source 110 becomes farther. Specifically, the area of the second region 126 can increase discretely as the separation distance between the diffusion member 120 and the light source 110 becomes farther. Thereby, the first region 125 can decrease discretely as the separation distance between the diffusion member 120 and the light source 110 becomes farther.

[0058] The second region 126 can be set using the following formula.

[0059]

Equation

[0060] Here, E means the horizontal or vertical length of the second region 126, D means the separation distance between the diffusion member 120 and the light source 110, θ means the divergence angle of the light emitting element 112, and t means the maximum separation distance between the centers of the light emitting elements arranged in the same row or column among the plurality of light emitting elements 112 included in the light source 110.

[0061] Based on the above formula 1, the second region 126 may have a minimum area in the shape of a rectangle having a horizontal length E1 and a vertical length E2. When the maximum separation distance t corresponding to the row or column of the light emitting elements 112 is the same, the second region 126 may be square-shaped, and when they are different from each other, the second region 126 may be rectangular-shaped. When the minimum area of the second region 126 is set in this way, the energy of the region where the light output is concentrated can be efficiently dispersed, and the manufacturing efficiency of the diffusion member 120 can be improved.

[0062] The separation distance between the diffusion member 120 and the light source 110 may be the perpendicular distance between the first surface of the light source 110 and the first surface of the diffusion member 120. The first surface of the light source 110 means the surface on which the light aperture is arranged. The first surface of the diffusion member 120 means the surface on which light is input from the light source 110 by each of the plurality of microlenses 122. Specifically, since the plurality of microlenses 122 are arranged in an embossed shape on the first surface of the diffusion member 120, the first surface of the diffusion member 120 can mean the surface connecting the points through which the optical axes of the plurality of microlenses 122 pass. Therefore, the separation distance between the diffusion member 120 and the light source 110 may be the perpendicular distance between a point through which the optical axis of the microlens 122 passes and the first surface of the light source 110.

[0063] The spherical surface of the microlens 122 can be calculated from the following formula 2.

[0064]

Equation

[0065] Here, C x and C yrepresents the curvature with respect to the x-axis and y-axis respectively, and k x and k y represent the conic constants with respect to the x-axis and y-axis respectively.

[0066] C x and C y can be proportional to the lengths of the image sensor in the x-axis and y-axis directions. That is, if the length in the y-axis direction of the image sensor is longer than the length in the x-axis direction, C x may be larger than C y . For example, when the length ratio of the x-axis and y-axis directions of the image sensor is a:b, the ratio of C x :C y can also be a:b. Specifically, when a:b is 3:4, the ratio of C x :C y is implemented as 3:4, that is, the curvature in the y-axis direction is increased to further diffuse the light, and the light can be diffused uniformly in the x-axis and y-axis directions.

[0067] Also, when k x and k y are designed to have the same value, it can be implemented such that the light diffusion distributions in the x-axis and y-axis directions have the same tendency.

[0068] When the coordinates of the point through which the optical axis passes on the spherical surface of the microlens 122 are (0,0), the height d of the microlens 122 part can be calculated by applying half of the diameter value (R / 2) of the microlens 122 to the variables x and y in the above formula 2.

[0069] FIG. 6 is a diagram for explaining the distance between the light source and the diffusion member with respect to the setting of the first region and the second region according to an embodiment of the present invention.

[0070] FIG. 6 shows the energy distribution of the diffusion member 120 having different separation distances from the light source 110. As shown in FIG. 6, in the case of D2, D3, D4, and D5, the area where the energy is distributed becomes wider than in the case of D1.

[0071] Table 1 below shows the amount of incident energy according to the separation distance between the light source 110 and the diffusion member 120 and the size of the microlens.

[0072] [Table 1]

[0073] Table 1 shows the number of microlenses onto which 99% or more of the total energy output from the light source is incident. For example, when the diffusion member 120 is an array of microlenses with a size of 50 [μm], at a separation distance of 0.5 [mm] between the light source 110 and the diffusion member 120, 99% or more of the energy is incident on 16×16 microlenses, while at 2.3 [mm], 99% or more of the energy is incident on 28×28 microlenses. That is, the larger the separation distance, the larger the number of microlenses onto which 99% or more of the energy is incident, indicating that the area of the second region expands. The same is true when microlenses with sizes of 100 [μm], 150 [μm], 200 [μm], and 300 [μm] are arrayed. However, since an array of microlenses of a predetermined size is arrayed, the area of the second region can increase discretely. That is, the area of the second region can be increased for each range of the predetermined separation distance. On the other hand, Table 1 shows that the size of the region onto which 99% or more of the total energy output from the light source is incident decreases according to the size of the microlenses. Table 1 assumes that microlenses of each size are arrayed in a region of the same size. Therefore, the microlenses with a size of 50 [μm] form the entire diffusion member 120 in a 48×48 array, and the microlenses with a size of 300 [μm] form the entire diffusion member 120 in an 8×8 array. At a separation distance of 2.3 [mm], when an array is configured with microlenses having a size of 50 [μm], 99% or more of the energy is incident on 28×28 microlenses out of 48×48 microlenses, whereas when an array is configured with microlenses having a size of 300 [μm], 99% or more of the energy is incident on 8×8 microlenses out of 8×8 microlenses.

[0074] The larger the number of microlenses into which 99% or more of the total energy output by the light source is incident, the smaller the amount of energy per microlens. Thus, it can be seen that the separation distance and the size of the microlens are preferably as small as possible. However, the separation distance cannot be increased without limit depending on the size of the terminal on which the distance measurement camera device 1000 is installed. Also, the size of the microlens cannot be reduced without limit when considering manufacturing costs and the like. Therefore, the first region and the second region must be efficiently set in consideration of the separation distance between the light source 110 and the diffusion member 120.

[0075] FIG. 7 is a diagram for explaining the divergence angle of the light emitting element according to an embodiment of the present invention.

[0076] Referring to FIGS. 6 and 7, first, the light source 110 and the diffusion member 120 are arranged to be separated by a predetermined distance D. Then, the light emitting element outputs light at a predetermined angle θ. When a virtual normal perpendicular to the substrate 111 is connected from the center of the light emitting element 112, the angle (θ / 2) formed by the virtual normal and the light is half of the divergence angle θ of the light output by the light emitting element 112. The plurality of light emitting elements 112 can all have the same standard, and the divergence angles θ at which the plurality of light emitting elements 112 output light can be the same as each other.

[0077] As described above, the area of the second region can be set based on the divergence angle of the light source 110. That is, the second region can be determined depending on how the divergence angle is set.

[0078] For example, as shown in FIG. 5, the light-emitting element can emit a predetermined amount of energy from -20 degrees to 20 degrees with respect to the optical axis. However, it can be seen that at an angle of -15 degrees or +15 degrees, or at an angle of -15 degrees or less or 15 degrees or more, the amount of energy is almost close to 0. That is, most of the energy exists within a predetermined angle with respect to the optical axis of the light-emitting element. Therefore, it is inefficient to set all the angles where the amount of energy is not 0 as the divergence angle of the light-emitting element, and it is efficient to set the angle at which a certain amount or more of energy is diverged as the divergence angle of the light-emitting element. Thus, the present invention can set the divergence angle of the light source 110 to the angle at which the light intensity is 1 / e 2 times the maximum light intensity of the light source 110. In this case, 99% of the light flux output from the light source 110 can be output within the divergence angle of the light source 110. The present invention can define the light with a light intensity up to 1 / e 2 times the maximum light intensity of the light source 110 as effective light, and define the angle up to that as the divergence angle.

[0079] On the other hand, the divergence angle can vary according to the magnitude of the current supplied to the light-emitting element. The light source can be supplied with a current within a predetermined range (between the magnitude of the first current and the magnitude of the second current), and the larger the supplied power, the larger the divergence angle can be. In FIG. 5, it shows that the light source 110 is supplied with a current in the range of 1.74 [A] to 5.23 [A]. It can be seen that the width of the relative light intensity graph when 5.23 [A] is supplied is wider than the width of the relative light intensity graph when 3.49 [A] is supplied. It can be seen that the width of the relative light intensity graph when 3.49 [A] is supplied is wider than the width of the relative light intensity graph when 1.74 [A] is supplied. Therefore, the divergence angle can be set based on the output of the light output when the maximum current is supplied to the light source 110. That is, when the light source 110 receives a current between the magnitude of the first current and the magnitude of the second current, the divergence angle of the light source can be set based on the output of the light output by the light source when the current of the magnitude of the second current is input.

[0080] Through FIGS. 8 and 9, the diffusion member 120 according to the first embodiment of the present invention is closely observed.

[0081] FIG. 8 is a diagram showing a diffusion member according to an embodiment of the present invention.

[0082] (a) of FIG. 8 is a plan view of a diffusion member 120 according to an embodiment, and (b) of FIG. 8 is a cross-sectional view of the diffusion member 120 according to an embodiment.

[0083] The diffusion member 120 according to an embodiment of the present invention includes a first region 125 and a second region 126. At this time, the second region 126 can include two sub-regions (126-1, 126-2). The plurality of sub-regions can include a first sub-region 126-1 and a second sub-region 126-2.

[0084] The first sub-region 126-1 can be arranged adjacent to the first region 125. And the second sub-region 126-2 can be separated from the first region 125 and arranged surrounded by the first sub-region 126-1. According to an embodiment, the diameter of the microlens arranged in at least one of the plurality of sub-regions can be the same as the diameter of the microlens arranged in the first region 125. As shown in FIG. 7, when the second region 126 includes the first sub-region 126-1 and the second sub-region 126-2, the diameter of the microlens arranged in the first sub-region 126-1 is the same as the diameter of the microlens arranged in the first region 125, and the diameter of the microlens arranged in the second sub-region 126-2 can be smaller than the diameter of the microlens arranged in the first region 125. For example, the diameter of the microlens arranged in the first sub-region 126-1 is 300 [μm], and the diameter of the microlens arranged in the second sub-region 126-2 can be 150 [μm]. On the other hand, the height formed by the microlens arranged in the first sub-region 126-1 and the microlens arranged in the second sub-region 126-2 can be the same.

[0085] FIG. 9 is a diagram showing an example of the light beam concentration degree according to FIG. 8.

[0086] Referring to Fig. 9, in the case of the microlens disposed in the first sub-region, energy is input within 0.5% of the total energy incident from the light source 110. And in the case of the second sub-region, the number of microlenses into which energy of 2.5% or more and less than 9.0% is input is 16, which corresponds to 1 / 16 of the area ratio of all the microlenses. This is at the level of 1 / 6 of the area ratio of the microlenses into which energy of 2.5% or more shown in Fig. 3 is input, indicating that the safety is extremely high.

[0087] Through Figs. 10 and 11, the diffusion member 120 according to the first embodiment of the present invention is examined in detail.

[0088] Fig. 10 is a diagram showing a diffusion member according to an embodiment of the present invention.

[0089] Fig. 10(a) is a plan view of the diffusion member 120 according to an embodiment, and Fig. 10(b) is a cross-sectional view of the diffusion member 120 according to an embodiment.

[0090] The diffusion member 120 according to an embodiment of the present invention includes a first region 125 and a second region 126. At this time, the second region 126 can include three sub-regions 126-1, 126-2, and 126-3. The plurality of sub-regions can include a first sub-region 126-1, a second sub-region 126-2, and a third sub-region 126-3. The third sub-region 126-3 includes the center of the diffusion member 120, can be separated from the first sub-region 126-1, and can be disposed surrounded by the second sub-region 126-2. That is, along the outer contour direction at the center of the diffusion member 120, the third sub-region 126-3, the second sub-region 126-2, the first sub-region 126-1, and the first region 125 can be sequentially arranged. The diameter of the microlens disposed in the third sub-region 126-3 can be smaller than the diameter of the microlens disposed in the second sub-region 126-2. Therefore, the diameter of the microlens disposed in the first region 125 is the same as the diameter of the microlens disposed in the first sub-region 126-1, the diameter of the microlens disposed in the second sub-region 126-2 is smaller than the diameter of the microlens disposed in the first sub-region 126-1, and the diameter of the microlens disposed in the third sub-region 126-3 can be smaller than the diameter of the microlens disposed in the second sub-region 126-2. For example, the diameter of the microlens disposed in the first sub-region 126-1 can be 300 [μm], the diameter of the microlens disposed in the second sub-region 126-2 can be 150 [μm], and the diameter of the microlens disposed in the third sub-region 126-3 can be 100 [μm]. On the other hand, the microlenses disposed in the first to third sub-regions 126-1 to 126-3 can form the same height with each other.

[0091] FIG. 11 is a diagram showing an example of the light beam concentration degree according to an embodiment of the present invention.

[0092] Referring to FIG. 11, the microlenses disposed in the first to third lower regions 126-1 to 126-3 receive energy within 0.5% of the total energy incident from the light source 110. Accordingly, all the microlenses included in the diffusing member 120 receive energy within 0.5%. As a result, even if some of the microlenses are damaged, the light output from the light source 110 is uniformly incident on all the microlenses, so that damage to the body by light can be prevented.

[0093] Through FIGS. 12 and 13, the simulation results according to the embodiments of the present invention are examined in detail.

[0094] FIG. 12 is a diagram showing simulation results in a diffusing member configured using only microlenses having a size of 300 [μm].

[0095] Looking closely at FIG. 12, when there is no damage to the microlenses (Ref), or when the microlenses are damaged in the outermost corner (Edge) or the region adjacent (Middle) to the outermost corner, the energy emitted from the damaged part of the microlenses is 1.1% or less, and the Eye Aperture Factor appears to be 179 or more. The said numerical value is a numerical value higher than 179 which is the standard of eye safety, and it can be ensured that no damage will occur even if the said light irradiates a human eye. However, when the microlenses are damaged in the region adjacent to the center of the diffusing member 120 (Center 2X2, 4X4), the energy emitted from the damaged part of the microlenses is 4.8% or more, and the Eye Aperture Factor appears to be 179 or less. In particular, both cases show numerical values that are 100 or more lower than the reference value of 179 of the Eye Aperture Factor, indicating that blindness may occur if the said light irradiates a human eye.

[0096] FIG. 13 is a diagram showing simulation results in a diffusing member according to an embodiment of the present invention.

[0097] (a) of FIG. 13 is the far-field according to the first embodiment, and (b) of FIG. 13 is the far-field according to the second embodiment. In both cases, it shows the case where the microlens is damaged in the area adjacent to the center of the diffusion member 120. In the case of (a) of FIG. 13, the Eye Aperture Factor is 125.2, and 4.55 [mW] is output from the damaged part based on 570 [mW] which is the total energy of the light source 110. In the case of (b) of FIG. 13, the Eye Aperture Factor is 194.8, and 2.93 [mW] is output from the damaged part based on 570 [mW] which is the total energy of the light source 110. In the case of the first embodiment, although the value is lower than 174 which is the reference value of the Eye Aperture Factor, the difference is 50 or less, and a serious injury such as blindness can be prevented. In the case of the second embodiment, the value is higher than 174 which is the reference value of the Eye Aperture Factor, indicating that there is no physical damage due to the damage of the microlens.

[0098] FIG. 14 is an exploded view of a distance measuring camera device according to an embodiment of the present invention.

[0099] The distance measuring camera device can include a light emitting part and a light receiving part. However, the configurations such as the substrate 10, the holder 30, and the shield can 50 are integrally formed and used in common for the light emitting part and the light receiving part, so it may be difficult to distinguish between the light emitting part and the light receiving part. In this case, it can be understood that each of the above configurations is a component of each of the light emitting part and the light receiving part. However, as a modification, the common configurations such as the substrate 10, the holder 30, and the shield can 50 can be provided separately for the light emitting part and the light receiving part respectively.

[0100] The light emitting part can include the substrate 10, the light source 20, the holder 30, the diffusion member 41, the diffuser ring 42, and the shield can 50. The light receiving part can include the substrate 10, the sensor 60, the filter 80, the holder 30, the lens 70, the barrel 71, and the shield can 50.

[0101] The substrate 10 can include a printed circuit board (PCB). The substrate 10 can be connected to a connector via the FPCB 91. The substrate 10 and the FPCB 91 can be formed of a rigid flexible PCB (RFPCB). The light source 20 and the sensor 60 can be arranged on the substrate 10. The substrate 10 can be arranged under the holder 30. The substrate 10 can include terminals. The terminals of the substrate 10 can be connected to the joint of the shield can 50. The terminals of the substrate 10 can include a plurality of terminals. The terminals of the substrate 10 can include two terminals.

[0102] The light source 20 can be arranged on the substrate 10. The light source 20 can be arranged in contact with the substrate 10. The light source 20 can be arranged on top of the substrate 10. The light source 20 can be arranged on the substrate 10. The light source 20 can correspond to the light source 110 described above.

[0103] The holder 30 can be arranged on the substrate 10. The holder 30 can be arranged in contact with the substrate 10. The holder 30 can be arranged on top of the substrate 10. The holder 30 can be arranged on the substrate 10. The holder 30 can be fixed to the substrate 10 by an adhesive. The holder 30 can accommodate the light source 20, the diffuser module 40, the sensor 60, and the filter 80 inside. The holder 30 can be a plastic injection molding. The holder 30 can be formed by injection.

[0104] The diffuser module 40 can include a diffusing member 41 and a diffuser ring 42. The diffuser module 40 can be integrally formed as a modification, but in this embodiment, in order to increase the moldability during injection molding, it can be manufactured separately into the diffusing member 41 and the diffuser ring 42. The diffusing member 41 and the diffuser ring 42 can be separated from each other.

[0105] The diffusing member 41 can be a diffuser lens. The diffusing member 41 can correspond to the diffusing member 120 described above. The diffusing member 41 can be disposed within the holder 30. The diffusing member 41 can be coupled to the holder 30. The diffusing member 41 can be fixed to the holder 30. The diffusing member 41 can be disposed on the optical path of the light emitted from the light source 20. The diffusing member 41 can be disposed on the light source 20. The diffusing member 41 can be disposed above the light source 20. The diffusing member 41 can be a plastic injection molding. The diffusing member 41 can be formed by plastic injection molding. The height of the upper end of the diffusing member 41 can correspond to the height of the upper end of the lens 70. The diffusing member 41 can be inserted upward in the vertical direction and coupled to the holder 30. At this time, the upward direction can be the direction from the lower part of the holder 30 to the upper part of the holder 30. A part of the diffusing member 41 can overlap with the holder 30 in the upward direction.

[0106] The diffuser ring 42 can be disposed within the holder 30. The diffuser ring 42 can be fixed to the holder 30. The diffuser ring 42 can be coupled to the holder 30. The diffuser ring 42 can be disposed under the diffusing member 41. The diffuser ring 42 can support the diffusing member 41. The diffuser ring 42 can be brought into contact with the diffusing member 41. The diffuser ring 42 can be a plastic injection molding. The diffuser ring 42 can be formed by plastic injection molding.

[0107] The shield can 50 can cover the body portion of the holder 30. The shield can 50 can include a cover. The shield can 50 can include a cover can. The shield can 50 can be a non-magnetic material. The shield can 50 can be formed of a metal material. The shield can 50 can be formed of a metal plate material. The shield can 50 can be electrically connected to the substrate 10. The shield can 50 can be connected to the substrate 10 through solder balls. Thereby, the shield can 50 can be grounded. The shield can 50 can block electromagnetic interference noise (EMI). At this time, the shield can 50 can be referred to as an "EMI shield can". In this embodiment, although high voltage is used inside the optical device and thus electromagnetic interference noise can be large, the shield can 50 can block the electromagnetic interference noise.

[0108] The sensor 60 can be arranged on the substrate 10. The sensor 60 can be arranged on the other side of the partition wall of the holder 30 on the substrate 10. That is, the sensor 60 can be arranged on the opposite side of the light source 20 with reference to the partition wall of the holder 30. The sensor 60 can sense infrared rays. The sensor 60 can sense light of a specific wavelength among the infrared rays. The sensor 60 can sense the light that has passed through the filter 80. The sensor 60 can sense the light in the wavelength band of the light source 20. Thereby, the sensor 60 can sense the light emitted from the light source 20 and reflected by the subject, and sense the 3D image information of the subject. Although the effective sensing area of the sensor 60 is arranged to correspond to the diffusing member 41, the sensor 60 can be arranged to be biased toward the partition wall side as a whole. Circuit patterns of the sensor 60 and the like can be arranged in the portion of the sensor 60 that is biased toward the partition wall side.

[0109] The lens 70 can be fixed in the barrel 71. The lens 70 can be a plastic injection product. The lens 70 can be formed by plastic injection. The lens 70 can include a plurality of lenses.

[0110] The filter 80 can be disposed between the lens 70 and the sensor 60. The filter 80 can be a band pass filter that allows light in a specific wavelength band to pass through. The filter 80 can allow infrared light to pass through. The filter 80 can allow light of a specific wavelength among infrared light to pass through. The filter 80 can allow light in the wavelength band of the light emitted by the light source 20 to pass through. The filter 80 can block visible light. The filter 80 can be coupled to the holder 30. A groove having a size corresponding to the filter 80 is formed in the holder 30, and the filter 80 can be inserted into the groove and fixed with an adhesive. An adhesive injection groove for injecting an adhesive between the filter 80 and the holder 30 can be further formed in the groove of the holder 30. The filter 80 can be disposed at a position lower than the position of the diffuser ring 42.

[0111] Although the embodiments have been mainly described above, this is merely an example and does 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 embodiments. For example, each component specifically shown in the embodiments can be implemented with modifications. And the differences related to such modifications and applications should be construed as being included in the scope of the present invention defined by the appended claims.

Claims

1. A light emitting unit, A light receiving unit including an image sensor, and The light emitting unit includes A light source in which a plurality of light emitting elements are arranged in an array, A diffusion member disposed on the light source and including a plurality of microlenses, and The diffusion member includes a first region and a second region, The first region is arranged to surround the second region, The second region A first sub-region adjacent to the first region and including microlenses having a first diameter, A second sub-region surrounded by the first sub-region, covering the upper portion in the optical axis direction of all the plurality of light emitting elements, and including microlenses having a second diameter smaller than the first diameter, a distance measuring camera device.

2. The distance measuring camera device according to claim 1, wherein the first diameter is the same as the diameter of the microlenses arranged in the first region.

3. The distance measuring camera device according to claim 1, wherein the area of the second region discretely increases as the separation distance between the diffusion member and the light source increases.

4. The distance measuring camera device according to claim 1, wherein the minimum area of the second region is set using the following formula. Here, E means the horizontal or vertical length of the second region, D means the separation distance between the diffusion member and the light source, θ means the divergence angle of the light source, and t means the separation distance between the centers of two light emitting elements arranged on the outermost side in the same row or column among the plurality of light emitting elements included in the light source.

5. The light source is input with a current between a first current magnitude and a second current magnitude, The distance measuring camera device according to claim 4, wherein the divergence angle of the light source is set based on the output of the light output by the light source when a current of the second current magnitude is input.

6. The divergence angle of the light source is 1 / e of the maximum light intensity of the light source. ２ 5. The distance measuring camera device according to claim 4, wherein e is an angle at which the light intensity is outputted twice as strong as the light intensity of the object, and e is a natural constant.

7. The distance measuring camera device according to claim 1, wherein the diameter of the microlenses located in the second region is 100 μm or more and 150 μm or less.

8. The distance measuring camera device according to claim 1, wherein the microlenses are arranged on the surface of the diffusion member on the light source side.

9. The distance measuring camera device according to claim 1, wherein the diameter of the microlenses located in the second sub-region is smaller than the diameter of the microlenses located in the first region.

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