LiDAR device

Abstract

A lidar device according to an embodiment of the present invention comprises: a light emitting unit for emitting an optical signal to an object; and a light receiving unit for receiving the optical signal reflected from the object. The light receiving unit includes: an image sensor including a light receiving surface having a long axis in a first direction; a first lens unit disposed on the image sensor; a window disposed on the first lens unit; and a filter disposed between the image sensor and the window, in which at least one of the filter and the window is tilted with respect to a light receiving surface of the image sensor with respect to a virtual first axis parallel to the long axis or a second axis tilted with respect to the first axis.

Description

Technical Field

[0001] This invention relates to a LiDAR device. Background Technology

[0002] LiDAR (Light Detection and Ranging) uses laser pulses emitted from a light-emitting unit and then reflected and returned from a target object to measure the distance to the target object or to form the shape of the target object. LiDAR is applied in various technical fields that require three-dimensional imaging. For example, LiDAR can be applied in various technical fields such as meteorology, aviation, aerospace, and vehicles. In recent years, the proportion of LiDAR in the field of autonomous driving has increased rapidly.

[0003] Typically, a LiDAR light emitting unit generates an output optical signal and uses this output optical signal to illuminate an object, a light receiving unit receives an input optical signal reflected from the object, and an information generation unit uses the input optical signal received by the light receiving unit to generate information about the object.

[0004] LiDARs can be broadly categorized into mechanical LiDARs and solid-state LiDARs. Mechanical LiDARs achieve a 360-degree field of view by rotating the light emitting and receiving units. Solid-state LiDARs can be, for example, microelectromechanical systems (MEMS) LiDARs, flash LiDARs, and optical phased array (OPA) LiDARs. In MEMS LiDARs, the tilt angle of the mirrors can be precisely changed via electrical signals. In flash LiDARs, an optical flash can be used, and a single large-area laser pulse can illuminate the environment in front. In OPA LiDARs, an optical phase modulator can control the speed of light passing through the lens, and thus, the optical wavefront shape can be controlled.

[0005] Typically, the light receiving unit of a mechanical LiDAR consists of an image sensor with a one-dimensional array structure, and is prone to artifacts due to double reflection. Noise caused by artifacts can provide incorrect information to the LiDAR instead of light reflected from actual objects, and this can produce virtual images in the point cloud (which are the result of object detection). Summary of the Invention

[0006] Technical issues

[0007] The present invention aims to provide a light detection and ranging (LiDAR) device that outputs collimated light to minimize noise caused by artifacts and prevent loss of the illuminated light.

[0008] The problems to be solved by the present invention are not limited to those described above, and those skilled in the art will clearly understand from the following description other problems not mentioned.

[0009] Technical solution

[0010] To achieve the above objectives, an optical detection and ranging (LiDAR) device according to an embodiment of the present invention includes: a light emitting unit configured to emit an optical signal toward an object; and a light receiving unit configured to receive an optical signal reflected from the object, wherein the light receiving unit includes: an image sensor including a light receiving surface having a long axis in a first direction; a first lens unit disposed on the image sensor; a window disposed on the first lens unit; and a filter disposed between the image sensor and the window, and at least one of the filter and the window is tilted relative to the light receiving surface of the image sensor about a virtual first axis parallel to the long axis or about a second axis tilted relative to the first axis.

[0011] The image sensor may include an array of pixels arranged in a first direction and a second direction perpendicular to the first direction, and the number of pixels arranged in the first direction may be greater than the number of pixels arranged in the second direction, and at least one of the filters and windows may be tilted about the first direction as a rotation axis.

[0012] Each of the filters and windows can be tilted about a first direction that serves as the axis of rotation.

[0013] The filter and window can be tilted within a range of 0.5 to 5 degrees about the first direction, which is the axis of rotation.

[0014] The filter and window can be tilted within a range of 1 to 3 degrees about the first direction, which is the axis of rotation.

[0015] One of the filters and windows can be tilted clockwise about a first direction that is the axis of rotation, and the other of the filters and windows can be tilted counterclockwise about the first direction that is the axis of rotation.

[0016] The LiDAR device may include a microlens array disposed between an image sensor and a first lens unit and having a long axis in a first direction, and at least one of the filters and windows may be tilted relative to the microlens array about a virtual axis parallel to the long axis of the microlens array.

[0017] The microlens array may include a plurality of microlenses arranged in a first direction and a second direction perpendicular to the first direction, and the number of microlenses arranged in the first direction may be greater than the number of microlenses arranged in the second direction.

[0018] Image sensors can include m An n-pixel array, where the ratio of m to n can be 8 or greater.

[0019] The filter may include a filter surface, which includes a first axis and a second axis.

[0020] A window may include a window surface, which includes a first axis and a second axis.

[0021] The first axis can be spaced apart from the long axis of the image sensor in the optical axis direction.

[0022] The second axis can be perpendicular to the first axis.

[0023] The LiDAR device includes: a light receiving unit that is rotated based on a rotation axis parallel to a first direction, wherein the light receiving unit includes an image sensor, a first lens unit spaced apart from the image sensor in an optical axis direction perpendicular to the first direction, a window spaced apart from a filter in the optical axis direction, and a filter disposed between the image sensor and the window, and at least one of the filter and the window is tilted about the first axis parallel to the first direction.

[0024] An image sensor may have a long axis in a first direction.

[0025] The image sensor can be configured to face the optical axis, and at least one of the filters and windows can be configured to face a direction deviating from the optical axis.

[0026] The LiDAR device may include a microlens array disposed between an image sensor and a first lens unit, and the microlens array may have a long axis in a first direction.

[0027] The LiDAR device includes a light emitting unit configured to emit optical signals toward an object and a light receiving unit configured to receive optical signals reflected from the object. The light receiving unit includes: an image sensor including a light receiving surface; a first lens unit disposed on the image sensor; a window disposed on the first lens unit; and a filter disposed between the image sensor and the window, wherein at least one of the light receiving surfaces of the filter and the window is tilted with respect to the image sensor.

[0028] At least one of the filters and windows may not be parallel to the light-receiving surface.

[0029] An image sensor may include: a pixel array, which includes a light-receiving surface; and a microlens array disposed on the pixel array.

[0030] At least one of the filters and windows can be tilted relative to the light-receiving surface of the microlens array.

[0031] According to an embodiment, a second lens unit that collects and outputs light emitted from a light source includes a first lens surface facing the light source unit and a second lens surface disposed opposite to the first lens surface. The first lens surface includes a plurality of first unit patterns arranged in a first direction and the first unit patterns extend in a second direction perpendicular to the first direction. The second lens surface includes a second unit pattern having a long axis extending in the first direction.

[0032] The first lens surface and the second lens surface can be asymmetrical relative to each other.

[0033] The pattern for the second unit can be aspherical.

[0034] The first unit pattern may have an arc shape based on an axis parallel to the second direction, and the second unit pattern may have an arc shape based on an axis parallel to the first direction.

[0035] The first unit pattern can be set such that the distance between the outermost radial point of a third direction perpendicular to the first and second directions and the axis parallel to the second direction is constant in the second direction.

[0036] A recessed portion extending from the surface of the first lens toward the surface of the second lens can be positioned between two adjacent first unit patterns.

[0037] The distance between multiple recessed portions in the second direction can be constant.

[0038] The surface of the second lens can be configured such that the distance between the outermost radial point based on the third direction and the axis parallel to the first direction is constant in the first direction.

[0039] The effective focal length (EFL) of the second lens surface can be 4 to 8 times that of the first lens surface.

[0040] The F-number of the second lens surface can be 0.2 to 0.5 times that of the first lens surface.

[0041] The LiDAR device according to an embodiment includes a light source unit that emits light and a second lens unit that collects and outputs light emitted from the light source. The second lens unit includes a first lens surface facing the light source unit and a second lens surface disposed opposite to the first lens surface. The first lens surface includes a plurality of first unit patterns arranged in a first direction and the first unit patterns extend in a second direction perpendicular to the first direction. The second lens surface includes a second unit pattern having a long axis extending in the first direction. The second lens unit collects and outputs light emitted from the light source.

[0042] The light source unit may include multiple light sources arranged in a first direction and configured to emit light in a third direction perpendicular to the first and second directions.

[0043] The first unit pattern can have an arc shape based on an axis parallel to the second direction, and can overlap with any of the multiple light sources in the third direction.

[0044] The length of the light source unit in the first direction can be shorter than the length of the first lens surface in the first direction.

[0045] When a reflective volume Bragg grating (VBG) is configured to be spaced apart from the second lens unit in a third direction, light reflected from the VBG can move toward the light source unit along the same optical path.

[0046] Multiple light sources can emit light with wavelengths ranging from 1350nm to 1450nm.

[0047] Beneficial effects

[0048] According to an embodiment of the present invention, a light detection and ranging (LiDAR) device for solving the above-mentioned problems can provide output collimated light to minimize noise caused by artifacts and prevent loss of the illuminated light.

[0049] The effects of the present invention are not limited to those described above, and those skilled in the art will clearly understand from the description of the claims other effects not mentioned.

[0050] Furthermore, the effects of the present invention can be described in more detail in the detailed description of the present invention, and are not necessarily limited to those described above. Attached Figure Description

[0051] The foregoing summary will be better understood not only by reading in conjunction with the accompanying drawings, but also by the following detailed description of exemplary embodiments of this application.

[0052] Exemplary embodiments are shown in the accompanying drawings to illustrate the purpose of this invention.

[0053] However, it should be understood that this application is not limited to the precise arrangement and mechanism shown.

[0054] Figure 1 This is a block diagram of a light detection and ranging (LiDAR) device according to an embodiment of the present invention.

[0055] Figure 2 This is a top view of an image sensor according to an embodiment of the present invention.

[0056] Figure 3 This is a bottom view of a microlens array according to an embodiment of the present invention.

[0057] Figure 4 This is a cross-sectional view of the image sensor and microlens array taken along a first direction according to an embodiment of the present invention.

[0058] Figure 5 This is a cross-sectional view of the image sensor and microlens array taken along the second direction according to an embodiment of the present invention.

[0059] Figure 6 This is a cross-sectional view of the light receiving unit taken along a first direction according to an embodiment of the present invention.

[0060] Figure 7 This is a cross-sectional view of the light receiving unit taken along the second direction according to an embodiment of the present invention.

[0061] Figure 8 An example of an artifact image is shown.

[0062] Figure 9 The optical path layout used to simulate the cause of artifacts is shown.

[0063] Figure 10 The results show the causes of simulated artifacts.

[0064] Figure 11 The simulation results are shown based on the tilt of the window and the filter.

[0065] Figure 12 The results of artifact analysis performed on each angle of the object are shown with the window and filter not tilted, and with the window not tilted and only the filter tilted by 2 degrees.

[0066] Figure 13 The results show the artifact analysis performed on each angle of the object while tilting the window within the range of -2 degrees to 2 degrees with the filter tilted by 2 degrees.

[0067] Figure 14 This is a view used to describe a light emitting unit according to an embodiment of the present invention.

[0068] Figure 15 This is a view used to describe the first surface of a LiDAR device according to an embodiment of the present invention.

[0069] Figure 16 This is a view used to describe the second surface of a LiDAR device according to an embodiment of the present invention.

[0070] Figure 17 This is a view used to describe the first unit pattern of a LiDAR device according to an embodiment of the present invention.

[0071] Figure 18 This is a view used to describe the second unit pattern of a LiDAR device according to an embodiment of the present invention.

[0072] Figure 19 This is a view used to illustrate the relationship between the light source and the first surface of the LiDAR device according to an embodiment of the present invention.

[0073] Figure 20 This is a view used to describe the first unit pattern and light emitting unit of a LiDAR device according to an embodiment of the present invention.

[0074] Figure 21 This is a view used to describe the optical path through the first surface of a LiDAR device according to an embodiment of the present invention.

[0075] Figure 22 This is a view used to describe the optical path through the second surface of a LiDAR device according to an embodiment of the present invention.

[0076] Figure 23 This is a view used to describe the focal point of a LiDAR device according to an embodiment of the present invention.

[0077] Figure 24 This is a view used to describe the propagation and reflection optical paths through the first surface of a LiDAR device according to an embodiment of the present invention.

[0078] Figure 25 This is a view used to describe the propagation and reflection optical paths through the second surface of a LiDAR device according to an embodiment of the present invention.

[0079] Figure 26 This is a perspective view of a LiDAR system according to an embodiment of the present invention.

[0080] Figure 27 This is an exploded view of a LiDAR system according to an embodiment of the present invention.

[0081] Figure 28 This is an exploded view of a LiDAR device according to an embodiment of the present invention. Detailed Implementation

[0082] In the following, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0083] However, the technical concept of the present invention is not limited to the embodiments to be described, but can be implemented in various different forms, and within the scope of the technical concept of the present invention, one or more components in the embodiments can be used by selective combination and substitution.

[0084] Furthermore, unless specifically defined and described, the terms (including technical and scientific terms) used in the embodiments of the present invention may be interpreted as having the meaning commonly understood by one of ordinary skill in the art to which the present invention pertains, and common terms such as those defined in dictionaries may be interpreted in light of the contextual meaning of the relevant art.

[0085] The terminology used in the embodiments of this invention is for descriptive purposes only and is not intended to limit the invention.

[0086] In this specification, unless the context clearly indicates otherwise, the singular form may include the plural form, and when described as “at least one (or more) of A, B and / or C”, it may include one or more of all possible combinations of A, B and C.

[0087] In addition, when describing the components of embodiments of the present invention, terms such as first, second, A, B, (a), (b) may be used.

[0088] These terms are used only to distinguish components from other components, and the nature, order, or sequence of components are not limited by these terms.

[0089] Additionally, when a component is described as “linked,” “coupled,” or “connected to” another component, the component is not only directly linked, coupled, or connected to the other component, but also “linked,” “coupled,” or “connected to” the other component when another component is arranged between the component and the other component.

[0090] Furthermore, when a component is described as forming or being positioned "above" or "below" another component, the term "above" or "below" includes not only when the two components are in direct contact with each other, but also when one or more other components are formed or arranged between the two components. Additionally, when a component is described as "above" or "below," the description may include meanings based on the upward and downward directions of a component.

[0091] The optical detection and ranging (LiDAR) device according to embodiments of the present invention can refer to a LiDAR device installed on a vehicle to measure the distance between the vehicle and an object, but is not limited thereto. The LiDAR device according to embodiments of the present invention can use the time-of-flight (ToF) principle or the phase-shift principle to extract depth information. In this specification, the LiDAR device may also be referred to as an information generation device, a depth information generation device, or a camera device.

[0092] Figure 1 This is a block diagram of a LiDAR device according to an embodiment of the present invention.

[0093] Reference Figure 1 According to an embodiment of the present invention, the LiDAR device 1000 includes a light emitting unit 100, a light receiving unit 200, an information generating unit 300, and a control unit 400.

[0094] The light emitting unit 100 can generate and output an optical signal in the form of a pulsed wave or a continuous wave. The continuous wave can be in the form of a sine wave or a square wave. By generating an output optical signal in the form of a pulsed wave or a continuous wave, the LiDAR device 1000 can detect the time difference or phase difference between the output optical signal output from the light emitting unit 100 and the input optical signal reflected from the target area and then input to the light receiving unit 200. In this specification, "output light" can refer to light output from the light emitting unit 100 and incident on an object, and "input light" can refer to light output from the light emitting unit 100 and reflected from the target area after reaching the target area and input to the light receiving unit 200. From the perspective of the target area, the output light can be the incident light, and the input light can be the reflected light. In this specification, the target area can be used interchangeably with the object or the target.

[0095] The light emitting unit 100 includes a light source unit 110 and a lens unit 120.

[0096] Light source unit 110 generates and outputs laser pulses. Light source unit 110 can use light-emitting diodes (LEDs) and can have multiple LEDs arranged in a predetermined pattern. Alternatively, light source unit 110 can include organic light-emitting diodes (OLEDs) or laser diodes (LDs). Alternatively, light source unit 110 can be a vertical-cavity surface-emitting laser (VCSEL). A VCSEL is a laser diode that converts an electrical signal into an optical signal and can output light with a wavelength of about 800 nm to 1000 nm (e.g., about 850 nm or about 940 nm). Light source unit 110 repeatedly flashes at predetermined time intervals to generate an output optical signal in the form of a pulsed wave or a continuous wave. The predetermined time interval can be the frequency of the output optical signal. Alternatively, light source unit 110 can include multiple light sources 111, which can emit light with a wavelength band of 1350 nm to 1450 nm, and the multiple light sources 111 can be LEDs as described above.

[0097] Lens unit 120 can collect light output from light source unit 110 and output the collected light to the outside. Lens unit 120 can be disposed above and spaced apart from light source unit 110. Here, "above light source unit 110" can refer to the side from which light is output from light source unit 110. Lens unit 120 may include at least one lens, and when lens unit 120 includes multiple lenses, the lenses can be aligned relative to a central axis to form an optical system. Here, the central axis can be the same as the optical axis of the optical system. Lens unit 120 may also include a diffusion member that receives light output from light source unit 110 and then outputs the received light by refraction or diffraction. This will be described in more detail below with reference to the accompanying drawings.

[0098] The light receiving unit 200 can receive optical signals reflected from the target area. In this case, the received optical signal can be an optical signal reflected from the target area output by the light emitting unit 100.

[0099] The light receiving unit 200 includes an image sensor, a lens unit 230 disposed on the image sensor, and a filter.

[0100] Optical signals reflected from the target area can pass through the lens unit 230 of the light receiving unit 200. The optical axis of the lens unit 230 of the light receiving unit 200 can be aligned with the optical axis of the image sensor. A filter can be disposed in the optical path between the target area and the image sensor. The filter can filter light with a predetermined wavelength range. The filter can transmit light of a specific wavelength. For example, the filter can transmit infrared light and block light outside the infrared band. The image sensor can receive the optical signal and output the received optical signal as an electrical signal. The image sensor can detect light with a wavelength corresponding to the wavelength of the light output from the light emitting unit 100. For example, the image sensor can detect infrared light.

[0101] Image sensors can be configured as a structure in which multiple pixels are arranged in a grid.

[0102] The optical receiving unit 200 and the optical emitting unit 100 can be arranged side by side. The optical receiving unit 200 can be positioned adjacent to the optical emitting unit 100. The optical receiving unit 200 can be configured to face the same direction as the optical emitting unit 100. Alternatively, the optical receiving unit 200 and the optical emitting unit 100 can be configured to face different directions. When the optical receiving unit 200 and the optical emitting unit 100 are configured to face different directions, an optical path redirection component can be further provided between the optical receiving unit 200 and the optical emitting unit 100.

[0103] The information generation unit 300 uses the input optical signal input to the light receiving unit 200 to generate information about the target region. The information about the target region may include three-dimensional information about the target region. For example, the information about the target region may include depth information or shape information about the target region. For example, the information generation unit 300 may calculate the depth information about the object using the time of flight required for the output optical signal output from the light emitting unit 100 to be reflected from the object and then input to the light receiving unit 200. For example, the information generation unit 300 may calculate the time difference between the output optical signal and the input optical signal using the electrical signal received by the image sensor, and use the calculated time difference to calculate the distance between the target region and the LiDAR device 1000. For example, the information generation unit 300 may calculate the phase difference between the output optical signal and the input optical signal using the electrical signal received by the image sensor, and use the calculated phase difference to calculate the distance between the target region and the LiDAR device 1000.

[0104] The control unit 400 controls the driving of the light emitting unit 100, the light receiving unit 200, and the information generating unit 300. The information generating unit 300 and the control unit 400 can be implemented in the form of a printed circuit board (PCB). Alternatively, the information generating unit 300 and the control unit 400 can be implemented in other forms. Alternatively, the control unit 400 can be included in a terminal or vehicle equipped with the LiDAR device 1000 according to an embodiment of the present invention. For example, the control unit 400 can be implemented as an application processor (AP) of a smartphone equipped with the LiDAR device 1000 according to an embodiment of the present invention, or as an electronic control unit (ECU) of a vehicle equipped with the LiDAR device 1000 according to an embodiment of the present invention.

[0105] The LiDAR device 1000 according to an embodiment of the present invention can be a mechanical LiDAR that rotates 360°. For this purpose, the LiDAR device 1000 may further include a rotating unit 500. The rotating unit 500 may further include a plate 510, on which a light emitting unit 100 and a light receiving unit 200 are mounted; and a motor 520 that rotates the plate 510. Therefore, the LiDAR device 1000 can have a 360° field of view (FOV).

[0106] In the following detailed description of the present invention, in order to distinguish between the lens unit 230 of the light receiving unit 200 and the lens unit 120 of the light emitting unit 100, the lens unit 230 of the light receiving unit 200 will be described as the first lens unit 230, and the lens unit 120 of the light emitting unit 100 will be described as the second lens unit 120.

[0107] Figure 2 This is a top view of an image sensor according to an embodiment of the present invention. Figure 3 This is a bottom view of a microlens array according to an embodiment of the present invention. Figure 4 This is a cross-sectional view of the image sensor and microlens array taken along a first direction according to an embodiment of the present invention. Figure 5 This is a cross-sectional view of the image sensor and microlens array taken along the second direction according to an embodiment of the present invention. Figure 6 This is a cross-sectional view of the light receiving unit taken along the first direction according to an embodiment of the present invention. Figure 7 This is a cross-sectional view of the light receiving unit taken along the second direction according to an embodiment of the present invention.

[0108] Reference Figures 2 to 7 The light receiving unit 200 included in the LiDAR device 1000 according to an embodiment of the present invention includes an image sensor 210, a first lens unit 230 disposed on the image sensor 210, a window 250 disposed on the first lens unit 230, and a filter 240 disposed between the image sensor 210 and the window 250. Although the present specification illustrates that the filter 240 is disposed between the first lens unit 230 and the window 250, the present invention is not limited thereto, and the filter 240 may be disposed between the image sensor 210 and the window 250. According to another embodiment of the present invention, a microlens array 220 disposed on the image sensor 210 may be further included. That is, the light receiving unit 200 included in the LiDAR device 1000 according to another embodiment of the present invention may include an image sensor 210, a microlens array 220 disposed on the image sensor 210, a first lens unit 230 disposed on the microlens array 220, a window 250 disposed on the first lens unit 230, and a filter 240 disposed between the image sensor 210 and the window 250.

[0109] According to an embodiment of the present invention, the image sensor 210 includes an active region and a non-active region surrounding the active region. The active region is a light-receiving surface comprising a pixel array. Here, the pixel array may be a single-photon avalanche diode (SPAD) array, and the SPAD array may include multiple SPADs. When a SPAD receives an optical signal, photons can be detected through the avalanche phenomenon.

[0110] Here, the image sensor 210 includes a pixel array arranged in a first direction and a second direction, and has a major axis in the first direction. That is, the number of pixels arranged in the first direction in the image sensor 210 can be greater than the number of pixels arranged in the second direction. For example, the image sensor 210 according to an embodiment of the present invention includes m An n-pixel array, where m can be greater than n. When the ratio of m to n is 8 or greater, the image sensor 210 can be referred to as a one-dimensional pixel array or a one-dimensional SPAD array.

[0111] According to embodiments of the present invention, the image sensor 210 may include a one-dimensional pixel array. For example, the image sensor 210 according to embodiments of the present invention may include 16 2-pixel array, 32 2-pixel array, 64 2-pixel array, 128 2-pixel array, 256 2-pixel array, 512 2-pixel array or 1024 2-pixel array.

[0112] When the light receiving unit 200 further includes a microlens array 220, the microlens array 220 is disposed on the image sensor 210 and spaced apart from the image sensor 210. The microlens array 220 includes a first surface 220A facing the image sensor 210 and a second surface 220B opposite to the first surface 220A, and a plurality of microlenses protrude from the first surface 220A to face the image sensor 210. For ease of description, the first surface 220A of the microlens array 220 can be referred to as the lower surface of the microlens array 220, and the second surface 220B of the microlens array 220 can be referred to as the upper surface of the microlens array 220.

[0113] According to an embodiment of the present invention, the first surface 220A of the microlens array 220 includes an active region 220A1, which includes a plurality of microlenses corresponding to the pixel array of the image sensor 210; a buffer region 220A2, which includes a plurality of microlenses configured to surround the active region 220A1; and a peripheral region 220A3, which is configured to surround the buffer region 220A2.

[0114] Here, the activation region 220A1 can be matched one-to-one with the pixel array. That is, when the image sensor 210 includes m When using an n-pixel array, the active region 220A1 can include m The image sensor 210 has n microlenses, and the pixels of the image sensor 210 can be matched one-to-one with the microlenses of the active region 220A1. Therefore, among the optical signals incident on the light receiving unit 200, the optical signals incident on the active region 220A1 can be detected by the image sensor 210 and used to identify objects. The optical signals incident on the light receiving unit 200 can be collected by the microlenses of the active region 220A1 of the microlens array 220, thereby improving the light receiving efficiency for each pixel. Therefore, the microlens array 220 can also be referred to as a sensor window.

[0115] Simultaneously, a buffer region 220A2 can be positioned around the active region 220A1 to surround it. For example, when the image sensor 210 includes m n-pixel array and active region 220A1 includes m When there are n microlenses, the first surface 220A of the microlens array 220 can include a total of (m+2a). (n+2b) microlenses, including a buffer region 220A2. Here, a and b can be the same or different from each other. For example, a and b can each be 1 or greater and 10 or less, preferably 1 or greater and 5 or less, and more preferably 2 or greater and 3 or less. For example, a can be 3 and b can be 2. As described above, when the first surface 220A of the microlens array 220 includes a buffer region 220A2 surrounding the activation region 220A1, the collection efficiency of the activation region 220A1 can be improved and the loss of optical signals can be reduced.

[0116] Meanwhile, the peripheral region 220A3 can be disposed around the buffer region 220A2 to surround the buffer region 220A2. In this case, the peripheral region 220A3 can be a flat surface. Therefore, the microlens array 220 can be integrated into the structure inside the image sensor 210 or the light receiving unit 200 through the peripheral region 220A3.

[0117] Reference Figure 6 and Figure 7The first lens unit 230, filter 240, and window 250 are disposed on the image sensor 210. Alternatively, the first lens unit 230, filter 240, and window 250 are disposed on the image sensor 210 and the microlens array 220. Here, the first lens unit 230 may include multiple lenses. For example, the first lens unit 230 may include two lenses spaced apart from each other, and is not limited thereto. The filter 240 disposed on the first lens unit 230 may be a bandpass filter. For example, the filter 240 may be a bandpass filter that transmits only infrared (IR) optical signals in the optical signals input to the receiving unit 200. Although not shown, the first lens unit 230 and filter 240 may be disposed in a lens barrel. Although the image sensor 210, microlens array 220, first lens unit 230 and filter 240 are illustrated as being arranged in sequence, the present invention is not limited thereto, and the image sensor 210, microlens array 220, filter 240 and first lens unit 230 may be arranged in this order.

[0118] Window 250 is located outside the lens barrel, and optical signals reflected from the object pass through window 250 and are then sequentially incident on filter 240, first lens unit 230, microlens array 220, and image sensor 210. Therefore, window 250 can be referred to as a glass window or external window. Optical signals output from light emitting unit 100 can also be output to the outside through window 250.

[0119] Meanwhile, as the optical signal reflected from the object is received by the image sensor 210 through the window 250, filter 240 and first lens unit 230, the optical signal can be reflected or refracted by the window 250, filter 240 and first lens unit 230, which can cause artifacts due to the virtual point cloud. Figure 8 An example of an artifact image is shown.

[0120] According to an embodiment of the present invention, at least one of the filter 240 and the window 250 is configured such that the active region of the light-receiving surface of the image sensor 210 or the microlens array 220 is tilted. Therefore, at least one of the filter 240 and the window 250 can be configured not to be parallel to the active region of the light-receiving surface of the image sensor 210 or the microlens array 220, thereby minimizing artifacts.

[0121] More specifically, as described above, the image sensor 210 includes a pixel array arranged in a first direction and a second direction, and the number of pixels arranged in the first direction is greater than the number of pixels arranged in the second direction. Similarly, the first surface 220A of the microlens array 220 may include a plurality of microlenses arranged in a first direction and a second direction perpendicular to the first direction, and the number of microlenses arranged in the first direction may be greater than the number of microlenses arranged in the second direction. Therefore, the first direction may refer to the long axis direction of the image sensor 210 or the microlens array 220, and the second direction may refer to the short axis direction of the image sensor 210 or the microlens array 220.

[0122] Here, at least one of the filter 240 and window 250 is tilted relative to the light-receiving surface of the image sensor 210 about a virtual first axis parallel to a first direction as the major axis or about a virtual second axis tilted relative to the first axis. Alternatively, at least one of the filter 240 and window 250 is tilted relative to the activation region of the microlens array 220 about a virtual first axis parallel to the first direction as the major axis or about a virtual second axis tilted relative to the first axis.

[0123] Here, "tilted about the first axis" can refer to rotation about an axis parallel to the first direction, which is the axis of rotation. That is, "tilted about the first axis" can refer to tilting about the first direction, and can also be expressed as rotation about the first direction, which is the axis. Here, the virtual first axis can be parallel to the long axis of the light-receiving surface of the image sensor 210 or the active region of the microlens array 220, and can be an axis spaced apart from the long axis of the light-receiving surface of the image sensor 210 or the active region of the microlens array 220 along the optical axis direction. Therefore, at least one of the filter surface of the filter 240 and the window surface of the window 250 can include the virtual first axis.

[0124] Here, the second axis can be a virtual second axis perpendicular to the first axis. That is, the virtual second axis can be parallel to the short axis of the light-receiving surface of the image sensor 210 or the active region of the microlens array 220, and can be an axis spaced apart from the short axis of the light-receiving surface of the image sensor 210 or the active region of the microlens array 220 in the optical axis direction. Therefore, at least one of the filter surface of the filter 240 and the window surface of the window 250 can include the virtual second axis.

[0125] Therefore, in this specification, the virtual first axis or virtual second axis included in at least one of the filter surface of the filter 240 and the window surface of the window 250 can be referred to as a rotation axis.

[0126] When at least one of the filter 240 and window 250 is tilted relative to the light-receiving surface of the image sensor 210 about a virtual first axis parallel to a first direction that is the major axis, Figure 6 This is a cross-sectional view of the light receiving unit 200 taken along the first direction, illustrating that the image sensor 210, filter 240, and window 250 are parallel to each other. Figure 7 This is a cross-sectional view of the light receiving unit 200 taken along the second direction, illustrating that the filter 240 is tilted relative to the image sensor 210 and the window 250 is tilted relative to the image sensor 210. That is, referring to... Figure 7 The filter 240 is tilted at a first angle θ1 relative to the direction parallel to the image sensor 210, and the window 250 is tilted at a second angle θ2 relative to the direction parallel to the image sensor 210.

[0127] Therefore, the image sensor 210 can be configured to face the optical axis direction, i.e., the third direction, while the filter 240 and window 250 can be configured to face a direction deviating from the optical axis direction, i.e., a direction tilted relative to the optical axis direction.

[0128] As described above, when the filter 240 and window 250 are set to tilt with respect to the long axis (i.e., with respect to the first direction as the axis of rotation) of the light-receiving surface of the image sensor 210 or the active region of the microlens array 220, artifact images can be eliminated from the active region 220A1 of the microlens array 220.

[0129] Here, the filter 240 and window 250 can be joined or fastened in an inclined state with respect to the long axis of the image sensor 210 (i.e., with respect to the first direction as the axis of rotation). For example, when the filter 240 is disposed in the lens barrel, the filter 240 can be joined to the inner wall of the lens barrel in an inclined state with respect to the long axis of the image sensor 210 (i.e., with respect to the first direction as the axis of rotation), or fixed to the lens barrel by a fastening member. Similarly, the window 250 can be joined to the housing or support member (not shown) of the LiDAR device 1000 in an inclined state with respect to the long axis of the image sensor 210 (i.e., with respect to the first direction as the axis of rotation), or fixed to the housing or support member (not shown) by a fastening member.

[0130] According to an embodiment of the invention, filter 240 is tilted clockwise about the rotation axis, and window 250 may be tilted counterclockwise about the rotation axis. Alternatively, according to an embodiment of the invention, filter 240 may be tilted counterclockwise about the rotation axis, and window 250 may be tilted clockwise about the rotation axis. Alternatively, according to an embodiment of the invention, filter 240 may be tilted clockwise about the rotation axis, and window 250 may be tilted clockwise about the rotation axis. Alternatively, according to an embodiment of the invention, filter 240 may be tilted counterclockwise about the rotation axis, and window 250 may be tilted counterclockwise about the rotation axis.

[0131] According to embodiments of the present invention, the filter 240 and window 250 can be tilted about the rotation axis in the range of 0.5 to 5 degrees, preferably in the range of 1 to 3 degrees, and more preferably in the range of 1.5 to 2.5 degrees. When the filter 240 and window 250 rotate about the rotation axis below the lower limit of the numerical range, it is difficult to obtain the effect of preventing artifacts, and when the filter 240 and window 250 rotate about the rotation axis above the upper limit of the numerical range, the amount of optical signal incident on the image sensor 210 may be reduced, thereby leading to difficulties in object recognition.

[0132] According to embodiments of the present invention, the angle θ1 of the filter 240 tilting about the rotation axis can be the same as or different from the angle θ2 of the window 250 tilting about the rotation axis. For example, the tilt direction of the filter 240 and the tilt direction of the window 250 can be the same as each other, and the tilt angle of the filter 240 and the tilt angle of the window 250 can be the same as each other. Alternatively, the tilt direction of the filter 240 and the tilt direction of the window 250 can be the same as each other, and the tilt angle of the filter 240 and the tilt angle of the window 250 can be different from each other. Alternatively, the tilt direction of the filter 240 and the tilt direction of the window 250 can be different from each other, and the tilt angle of the filter 240 and the tilt angle of the window 250 can be the same as each other. For example, the filter 240 can be rotated 2 degrees clockwise about a first direction of the image sensor 210 as an axis, and the window 250 can be rotated 2 degrees counterclockwise about the first direction of the image sensor 210 as an axis. Alternatively, the filter 240 can be rotated 2 degrees counterclockwise about a first direction of the image sensor 210 as an axis, and the window 250 can be rotated 2 degrees clockwise about the first direction of the image sensor 210 as an axis. Alternatively, the tilt direction of the filter 240 and the tilt direction of the window 250 can be different from each other, and the tilt angle of the filter 240 and the tilt angle of the window 250 can also be different from each other.

[0133] As described above, when the filter 240 and window 250 are set to tilt about the rotation axis, artifact images in the active area 220A1 of the microlens array 220 can be avoided, and the accuracy of object recognition can be improved.

[0134] Figure 9 It is an optical path layout used to simulate the causes of artifacts. Figure 10 The results show the causes of simulated artifacts.

[0135] Reference Figure 9 and Figure 10 Artifact #1 is an artifact that occurs when double reflection is caused between lens L2, which is closer to image sensor 210, and window 250, one of the two lenses included in the first lens unit 230. Artifact #2 is an artifact that occurs when double reflection is caused between lens L2, which is closer to image sensor 210, and filter 240, one of the two lenses included in the first lens unit 230. Artifact #3 is an artifact that occurs when double reflection is caused between sensor window and window 250 on the image sensor 210 side. Artifact #4 is an artifact that occurs when double reflection is caused between sensor window and filter 240 on the image sensor 210 side. And artifact #5 is an artifact that occurs when double reflection is caused between sensor window on the image sensor 210 side and lens L2, which is closer to image sensor 210, one of the two lenses included in the first lens unit 230.

[0136] like Figure 10 As shown, artifacts #3 and #4 are most clearly indicated. In the one-dimensional sensor array structure according to an embodiment of the present invention, it can be seen that the artifacts with the greatest impact are caused by the double reflection of the filter 240 and the window 250.

[0137] Figure 11 The simulation results are shown based on the tilt of the window and the filter.

[0138] Reference Figure 11In the example where neither the filter nor the window is tilted (i.e., in the example where the filter 240 is tilted 0 degrees and the window 250 is tilted 0 degrees about the first axis parallel to the first direction which is the major axis of the image sensor 210), it can be seen that the artifact image is clearly present on the active region of the one-dimensional sensor array structure. Next, in the example where only the filter is tilted (i.e., in the example where the filter 240 is tilted only 2 degrees clockwise and the window 250 is tilted 0 degrees about the first axis parallel to the first direction which is the major axis of the image sensor 210), it can be seen that one artifact image is avoided outside the active region of the one-dimensional sensor array structure, but another artifact image remains within the active region. Next, in the example where only the window is tilted (i.e., in the example where window 250 is tilted 2 degrees counterclockwise and filter 240 is tilted 0 degrees about a first axis parallel to the first direction that is the major axis of image sensor 210), it can be seen that one artifact image is avoided outside the active region of the one-dimensional sensor array structure, but another artifact image remains in the active region. In contrast, in the example where both the filter and the window are tilted (i.e., in the example where filter 240 is tilted 2 degrees clockwise and window 250 is tilted 2 degrees counterclockwise about a first axis parallel to the first direction that is the major axis of image sensor 210), it can be seen that the artifact image is formed outside the active region of the one-dimensional sensor array structure.

[0139] More specifically, Figure 12 The results of artifact analysis performed for each angle of the object are shown with the window and filter both untilted and with the window untilted and only the filter tilted by 2 degrees about a first axis parallel to the first direction which is the major axis of the image sensor 210. (Refer to...) Figure 12 As can be seen, compared to the case where neither the window nor the filter is tilted, when the filter is tilted by 2 degrees, the artifact phenomenon is alleviated at all angles of the object.

[0140] Next, Figure 13 The results show the artifact analysis performed on each angle of the object while the filter is tilted by 2 degrees about a first axis parallel to the long axis of the image sensor 210, within a range of -2 degrees to 2 degrees. (Refer to...) Figure 13 It can be seen that when the window is tilted while the filter is tilted, artifact images are formed outside the active region of the one-dimensional sensor array structure. In particular, it can be seen that when the window is tilted by 2 degrees, compared with the case of the window being tilted by 1 degree, the artifact images are formed at a greater distance from the active region of the one-dimensional sensor array structure.

[0141] The light emitting unit 100 according to this embodiment includes a light source unit 110 and a second lens unit 120, and can be referred to... Figures 14 to 19 The light source unit 110 and the second lens unit 120 are described in detail.

[0142] Specifically, Figure 14 This is a view used to describe a light emitting unit according to an embodiment of the present invention. Figure 15 This is a view used to describe the first lens surface of a LiDAR device according to an embodiment of the present invention. Figure 16 This is a view used to describe the second lens surface of a LiDAR device according to an embodiment of the present invention. Figure 17 This is a view used to describe the first unit pattern of a LiDAR device according to an embodiment of the present invention. Figure 18 This is a view used to describe the second unit pattern of a LiDAR device according to an embodiment of the present invention, and Figure 19 This is a view used to illustrate the relationship between the light source and the first lens surface of the LiDAR device according to an embodiment of the present invention.

[0143] First, refer to Figures 14 to 19 ,like Figure 14 As shown, a LiDAR device according to an embodiment of the present invention may include a light source unit 110, a second lens unit 120, and a volume Bragg grating V, which are arranged side by side in a third-order orientation.

[0144] Here, the volume Bragg grating V is illustrated to describe the optical path according to an embodiment of the present invention that will be described below, and the volume Bragg grating V is only provided to describe another embodiment of the present invention and the movement of the optical path according to an embodiment of the present invention, and the present invention is not necessarily limited to the volume Bragg grating V as described above.

[0145] First, the light source unit 110 can emit light to the second lens unit 120, and can be a collection of multiple light sources 111 that emit light. Here, the multiple light sources 111 can be arranged in a first direction, each extending in a third direction. In addition, the light source 111 can be a diode that emits light from a side surface (i.e., at the end in the third direction), but is not limited to this.

[0146] That is, the LiDAR device according to an embodiment of the present invention may include a second lens unit 120, which includes a first lens surface 121 disposed facing the light source unit 110 and a second lens surface 126 spaced apart from the first lens surface 121 and disposed facing the first lens surface 121. The first lens surface 121 includes a plurality of first unit patterns 122 arranged in a first direction perpendicular to the third direction. The first unit patterns 122 extend in a second direction perpendicular to the first direction. The second lens surface 126 includes a second unit pattern 127 extending in the first direction.

[0147] In this case, the third direction can refer to the direction from the light source unit 110 to the second lens unit 120, the first direction can be perpendicular to the third direction and can refer to the direction in which the first unit pattern 122 is arranged, and the second direction can be perpendicular to the first direction and the third direction and can refer to the direction in which the first unit pattern 122 extends.

[0148] Furthermore, the length of the light source unit 110 in the first direction can be relatively shorter than the length of the first lens surface 121 in the first direction, thereby preventing light loss due to errors occurring during the manufacturing process or due to the divergence angle generated from the light source unit 110, and the present invention is not limited to the above.

[0149] At the same time, such as Figure 15 and Figure 16 As shown, the first lens surface 121 and the second lens surface 126 have asymmetrical shapes and may have aspherical shapes.

[0150] This may be because the direction in which the light incident on the first lens surface 121 is collected as collimated light is different from the direction in which the light is collected as collimated light after passing through the second lens surface 126.

[0151] In short, on the first lens surface 121 according to an embodiment of the present invention, light emitted by the light source unit 110 is incident on and collected in a first direction, and on the second lens surface 126, the emitted light can be collected onto the second lens surface 126.

[0152] That is, while passing through the first lens surface 121 and the second lens surface 126, the light emitted by the light source unit 110 can be emitted in the third direction as collimated light parallel to the first and second directions.

[0153] In this case, as described above, a plurality of first unit patterns 122 may be arranged in a first direction to form a first lens surface 121, and a single second unit pattern 127 may extend in the first direction to form a second lens surface 126.

[0154] In addition, multiple first unit patterns 122 can extend in the second direction.

[0155] This arrangement can reflect the characteristics of the first lens surface 121 that collects light in the first direction and the characteristics of the second lens surface 126 that collects light in the second direction.

[0156] For example, due to the characteristics of light passing through the raised pattern, the light path can be changed according to the refractive index when passing through the raised surface, and in the case of the first lens surface 121, since it is necessary to collect light in the first direction, light can be collected through multiple first unit patterns 122, which can prevent light loss caused by the divergence angle of light due to the characteristics of the light source unit 110 that emits light.

[0157] Meanwhile, in the detailed description of the present invention, it is mentioned that each of the first unit pattern 122 and the second unit pattern 127 according to the present invention is aspherical, but this is based on the case that the first unit pattern 122 is regarded as a single lens and is referred to as an aspherical shape, and the first lens surface 121 formed by the set of the first unit patterns 122 can correspond to a surface with multiple curvatures formed by the set of aspherical first unit patterns 122.

[0158] That is, the fact that the first lens surface 121 is aspherical means that the first lens surface 121 has a lens shape other than spherical, and does not necessarily mean that the first lens surface 121 is formed into an aspherical shape with a single curvature.

[0159] In the accompanying drawings and detailed description described below, as described above, the first lens surface 121 is a collection of first unit patterns 122 that each have an aspherical shape when defined as a single lens, and is therefore referred to as an aspherical shape; the second lens surface 126 is an extension of the second unit pattern 127, and is therefore an aspherical shape; and the fact that the first lens surface 121 and the second lens surface 126 are aspherical can mean that each of the first lens surface 121 and the second lens surface 126 is not spherical or partially spherical based on its overall shape.

[0160] At the same time, such as Figure 17 As shown, multiple first unit patterns 122 can be arranged on the first lens surface 121 in a first direction.

[0161] In addition, the first unit pattern 122 can be configured to have an arc shape based on an axis parallel to the second direction.

[0162] More specifically, when a third axis 123 parallel to the second direction is defined relative to the second lens unit 120, the first unit pattern 122 may have an arcuate shape at a first distance R1 from the third axis 123, and the recessed portion 124 may be disposed between adjacent first unit patterns 122.

[0163] In this case, the first distance R1 does not represent part of the circle formed based on the third axis 123, but rather illustrates part of the axis that serves as a reference for the arcuate shape formed by the first unit pattern 122, and the third axis 123 is any one of a plurality of reference axes on which the first unit pattern 123 is formed, but the set of reference axes forming the first unit pattern 122 can be arranged together with the third axis 123 in a third direction.

[0164] Here, the distance between adjacent recessed portions 124 can be the same, and by defining the outermost point of the first unit pattern 122 in the third direction (more specifically, the outermost point in the direction facing the light source unit 110) as the first unit pattern 122a, the distance between adjacent first unit patterns 122a can be the same.

[0165] In other words, the first unit pattern 122a can be the radial outermost point of the first unit pattern 122 in the third direction.

[0166] That is, the first unit pattern 122 may have an arc shape with a first distance R1 based on the third axis 123, and the first unit pattern 122a may be set facing the light source unit 110 in the third direction. The distance between the first unit patterns 122a may be the same, and the distance between the recessed portions 124 set between the first unit patterns 122 may also be the same.

[0167] Therefore, the light emitted by the light source 111 can have uniform collimated light.

[0168] In addition, the first unit pattern 122 can be columnar in shape, wherein the distance between the third axis 123 and the first unit pattern 122a is the same in the second direction.

[0169] That is, in the first unit pattern 122, the distance between the third axis 123 and the first unit pattern 122a in the second direction can be the same as the first distance R1.

[0170] At the same time, such as Figure 18 As shown, the second unit pattern 127 of the second lens surface 126 can be similar to the first lens surface 121 and is configured to have an arc shape based on an axis parallel to the first direction.

[0171] More specifically, when a fourth axis 128 parallel to the first direction is defined based on the second lens unit 120, the second unit pattern 127 may have an arcuate shape that is a second distance R2 from the fourth axis 128.

[0172] Here, the second unit pattern 127 can be formed at the outermost point that is relatively far away from the light source unit 110 in the third direction, and when the outermost point of the second unit pattern 127 is defined as the second outermost point 127a, the distance between the fourth axis 128 and the second outermost point 127a can be the second distance R2.

[0173] Therefore, the light passing through the surface 121 of the first lens can be uniformly collimated light in the first and second directions.

[0174] In other words, the second outermost point 127a can be the radial outermost point of the second unit pattern 127 in the third direction.

[0175] Here, the second unit pattern 127 can be a semi-cylindrical shape, wherein the distance between the fourth axis 128 and the second outermost point 127a is the same in the first direction.

[0176] That is, in the second unit pattern 127, the distance between the fourth axis 128 and the second outermost point 127a in the first direction can be the same as the second distance R2.

[0177] In summary, since multiple first unit patterns 122 are disposed in the first direction, the first lens surface 121 can be configured to have multiple raised surfaces in the first direction, and since the second lens surface 126 extends as a single second unit pattern 127 in the first direction, the second lens surface 126 can be configured to have a single raised surface in the second direction.

[0178] In this case, the second distance R2 does not represent part of the circle formed based on the fourth axis 128, but rather illustrates part of the axis that serves as a reference for the arcuate shape formed by the second unit pattern 127, and the fourth axis 128 is any one of a plurality of reference axes that form the second unit pattern 127, but the set of reference axes that form the second unit pattern 127 can be arranged together with the fourth axis 128 in a third direction.

[0179] Here, the third axis 123 forming the first unit pattern 122 and the fourth axis 128 forming the second unit pattern 127 can be set to be perpendicular to each other.

[0180] More specifically, since the first lens surface 121 collects light in the first direction and the second lens surface 126 collects light in the second direction, the curvature of the first lens surface 121 and the second lens surface 126 needs to be formed asymmetrically, and in order to collect light in a single direction for each surface, it may be preferred to employ an aspherical shape in the first lens surface 121 and the second lens surface 126 according to an embodiment of the present invention.

[0181] That is, since multiple light sources 111 are arranged in the first direction, the first lens surface 121 that collects light in the first direction may have multiple first unit patterns 122 arranged in the first direction.

[0182] Furthermore, the light source 111 can be defined as emitting from a single point based on a second direction, and therefore, unlike the first lens surface 121, the second lens surface 126 can be formed as a single second unit pattern 127.

[0183] Here, in the second direction, the light source 111 can have a single arrangement and the second lens surface 126 can be formed as a single second unit pattern 127, thereby enabling the output of uniform collimated light through the single second unit pattern 127.

[0184] In this case, in order to distinguish the second lens surface 126 and the second unit pattern 127, the second lens surface 126 may refer to the surface of the semi-cylinder formed by the second unit pattern 127, and the second unit pattern 127 may refer to the pattern forming the semi-cylinder.

[0185] That is, the second lens surface 126 can refer to the surface itself, and the second unit pattern 127 can refer to the pattern that forms the second lens surface 126 itself, which is also the case in the following description, and the second unit pattern 127 and the second lens surface 126 can have the same meaning in cross-sectional shape.

[0186] However, the first lens surface 121 may be a surface formed by a collection of multiple first unit patterns 122. The first lens surface 121 may refer to the surface itself formed by the multiple first unit patterns 122, and the first unit pattern 122 may refer to the pattern formed when the cross-sectional shape of the second lens unit 120, taken along the first direction, is viewed in the second direction.

[0187] That is, when the cross-sectional shape of the second lens unit 120 is observed in the second direction, the collection of a plurality of first unit patterns 122 forms the first lens surface 121, and when the cross-sectional shape of the second lens unit 120 is observed in the first direction, the shape of the first unit pattern 122 changes according to the cut cross-sectional shape. Therefore, the cross-sectional shape of the second lens unit 120 observed in the first direction can be referred to as the first lens surface 121.

[0188] At the same time, such as Figure 19 As shown, based on the foregoing, the light source unit 110 includes a plurality of light sources 111, and the plurality of light sources 111 can emit light from the side surface.

[0189] Specifically, the light source 111 can emit light toward the first lens surface 121, and the light source 111 can be configured to overlap with the first unit pattern 122 in a third direction.

[0190] More specifically, the third axis 123 forming the first unit pattern 122 and the light source 111 overlap in the third direction, and in the third direction, the light source 111, the first unit pattern 122a and the third axis 123 can be arranged side by side to overlap.

[0191] That is, in the third direction, the recessed portion 124 and the light source 111 do not overlap each other, and can be configured in a manner similar to the recessed portion 124 being located between the light sources 111 in the first direction.

[0192] Therefore, the light emanating from the light source 111 can pass through the first lens surface 121 and be emitted as uniform collimated light based on the first direction.

[0193] For a more detailed description based on the aforementioned arrangement and configuration, please refer to... Figures 20 to 25 .

[0194] Specifically, Figure 20 This is a view used to describe the first unit pattern and light emitting unit of a LiDAR device according to an embodiment of the present invention. Figure 21 This is a view used to describe the optical path through the first lens surface of a LiDAR device according to an embodiment of the present invention. Figure 22 This is a view used to describe the optical path through the second lens surface of a LiDAR device according to an embodiment of the present invention. Figure 23 This is a view used to describe the focal point of a LiDAR device according to an embodiment of the present invention. Figure 24 This is a view used to describe the propagation and reflection optical paths through the first lens surface of a LiDAR device according to an embodiment of the present invention. Figure 25 This is a view used to describe the propagation and reflection optical paths through the second lens surface of a LiDAR device according to an embodiment of the present invention.

[0195] First, such as Figure 20 As shown, multiple light sources 111 can be arranged in a first direction, multiple first unit patterns 122 can be arranged in the first direction, and the first unit patterns 122 and the light sources 111 can overlap each other in a third direction.

[0196] In addition, the light source 111 emits light from the side surface, and a recessed space in the second direction can be provided between the light sources 111.

[0197] Therefore, the light source unit 110 and the first lens surface 121 can be configured such that the first unit pattern 122 and the light source 111 overlap each other, and the recessed portion 124 and the recessed space of the light source unit 110 overlap each other.

[0198] Here, as described above, the first lens surface 121 collects light in the first direction, and therefore, as Figure 21 As shown, the light emitted by the light source 111 can be incident on the surface 121 of the first lens with a divergence angle in the first direction.

[0199] In this case, light incident on the first lens surface 121 can be collected in the first direction by multiple first unit patterns 122, and in the process from the first lens surface 121 toward the second lens surface 126, a set of light paths that are collected in the first direction but not in the second direction can be formed.

[0200] Meanwhile, as the light emitted by the light source unit 110 passes through the first lens surface 121 at a divergence angle in the second direction and then through the second lens surface 126, the light can be collected in the second direction.

[0201] That is, while passing through the first lens surface 121 and the second lens surface 126, a light path collection can be formed in the first direction and the second direction, and the light emitted by the light source unit 110 can be emitted as collimated light through the second lens unit 120.

[0202] When collimated light is emitted in this manner, it prevents the loss of light beyond that of the separate lens used to adjust the field of view, thereby improving efficiency.

[0203] Meanwhile, to describe the invention in more detail, the light source 111, the second lens unit 120, and the volume Bragg grating V can be configured similarly to... Figure 1 The method is set up by a third party.

[0204] In this case, the light source 111 that emits light forms the focal point F of the second lens unit 120 according to an embodiment of the present invention, and the characteristics of the first lens surface 121 and the second lens surface 126 can be as follows.

[0205] [Table 1]

[0206] First, the light emitted by the light source 111 can be incident on the first lens surface 121 with a divergence angle of 25.5 degrees and on the second lens surface 126 with a divergence angle of 77.9 degrees.

[0207] More specifically, the light emitted by the light source 111 can diverge at 25.5 degrees in a first direction where the light is collected on the first lens surface 121, and diverge at 77.9 degrees in a second direction where the light is collected on the second lens surface 126. The light incident at 25.5 degrees through a plurality of first unit patterns 122 arranged on the first lens surface 121 can be collected in the first direction and output as collimated light, and the light passing through the second lens surface 126 in the second direction can be collected in the second direction and output as collimated light.

[0208] Furthermore, since the light passing through the first lens surface 121 and the second lens surface 126 according to the embodiment of the present invention has a divergence angle of 25.5 degrees in the first direction and a divergence angle of 77.9 degrees in the second direction as described above, the refractive index of the second lens unit 120 can be 1.89406, so that the light passing through the second lens unit 120 is output as collimated light.

[0209] Therefore, according to an embodiment of the present invention, the second lens unit 120 can collect the light emitted by the light source 111 in the first direction and the second direction and output the light as collimated light, thereby providing the effect of preventing the loss of light that deviates from the second lens unit 120.

[0210] That is, observe the refractive index of the second lens unit 120, and hope that it has a refractive index in the range of 1.8 to 2.0.

[0211] Additionally, the design divergence angle of the light source 111 can be calculated relative to the design numerical aperture (numerical aperture; hereinafter, "design NA") described below using Equation 1.

[0212] [Equation 1]

[0213] [Design divergence angle of light source 111] = 2 n sin (designed NA)

[0214] This indicates that the design of the NA adjusts the angular range at which it can receive or emit light at the aperture, so that the light output as collimated light is reflected from the object without loss, thereby obtaining higher resolution through the light.

[0215] Here, the designed NA can be described by Equations 2 and 3 below.

[0216] [Equation 2]

[0217] [Design NA] = 1 / (2) F-number)

[0218] [Equation 3]

[0219] [F number] = Focal point (F) / Diameter (D)

[0220] As shown in the figure, the NA is designed to be inversely proportional to the F number. Since the F number is inversely proportional to the diameter of the incident lens surface, the F number of the first lens surface 121 relative to the adjacent light source 111 can be greater than the F number of the second lens surface 126.

[0221] As described above, this can be a preferred design for obtaining higher resolution by preventing the loss of light during the process of light emitted by the light source 111 being emitted to or reflected from an object and then incident, and is not necessarily limited to the above description.

[0222] Meanwhile, when the F number of the first lens surface 121 of the second lens unit 120 is defined as FNO-1 and the F number of the second lens surface 126 is defined as FNO-2, FNO-1 and FNO-2 can fall within the range of the following equation 4.

[0223] [Equation 4]

[0224] 0.2 <FNO-2 / FNO-1 <0.5

[0225] That is, according to Equation 4, the F number of the second lens surface 126 can be 0.2 to 0.5 times the F number of the first lens surface 121.

[0226] This can correspond to a preferred form based on the arrangement of light sources 111 in the first direction, the difference in the form of multiple first unit patterns 122 arranged in the first direction, and the difference between the diameter of the first lens surface 121 in the first direction and the diameter of the second lens surface 126 in the second direction, thereby enabling the output of uniform collimated light.

[0227] Meanwhile, when the effective focal length of the first lens surface 121 of the second lens unit 120 is defined as EFL-1 and the effective focal length of the second lens surface 126 is defined as EFL-2, EFL-1 and EFL-2 can fall within the range of the following Equation 5.

[0228] [Equation 5]

[0229] 4 <EFL-2 / EFL-1 <8

[0230] That is, according to Equation 5, the effective focal length of the second lens surface 126 can be 4 to 8 times the effective focal length of the first lens surface 121.

[0231] These values ​​can correspond to the values ​​when the first lens surface 121 and the second lens surface 126 are each used as references. Due to the difference in effective focal length caused by the difference in the arcuate shape of the first lens surface 121 and the second lens surface 126, the light path can be output as collimated light. By outputting uniform collimated light, high resolution can be output without loss of light.

[0232] Meanwhile, the back focal length BFL of the first lens surface 121 can be based on the distance to the focal point F corresponding to the first unit pattern 122a, and in the case of the second lens surface 126, since there is no final lens surface for determining the back focal length BFL, the first unit pattern 122a of the first lens surface 121 can be used similarly as a reference.

[0233] That is, the back focal length of the first lens surface 121 and the back focal length BFL of the second lens surface 126 can ultimately be the same as the distance between the back surface B of the second lens unit 120 and the focal point F.

[0234] However, from a broader perspective, the back focal lengths BFL of the first lens surface 121 and the second lens surface 126 are the same, but since the back focal length BFL corresponds to the distance between the light source 111 and the second lens unit 120, the distance of the back focal length BFL is preferably in the range of 0.3 to 1.0.

[0235] When the back focal length (BFL) is designed within a specified range, it can prevent light loss at the first lens surface 121 due to the divergence angle of the light emitted by the light source 111, and can output collimated light without loss of light, thereby enabling high resolution output.

[0236] Meanwhile, according to an embodiment of the present invention, the first distance R1 of the first lens surface 121 of the second lens unit 120 can correspond to the distance between the third axis 123 forming the first unit pattern 122 and the first outermost point 122a as described above, and assuming that the direction of light travel in the third direction is negative and the direction toward the light source 111 is positive relative to the second lens unit 120, the first distance R1 can be 0.4810.

[0237] In addition, the second distance R2 of the second lens surface 126 of the second lens unit 120 can correspond to the distance between the fourth axis 128 forming the second unit pattern 127 and the first outermost point 127a as described above, and assuming that the direction of light travels in the third direction is negative and the direction toward the light source 111 is positive relative to the second lens unit 120, then the second distance R2 can be -2.7018.

[0238] This may be due to the size difference between the first unit pattern 122, which corresponds to a relatively small unit pattern, and the second unit pattern 126, which has a unit pattern larger than the first unit pattern 122. It may also be because, as described above, the divergence angle of light incident on the first lens surface 121 in the first direction is different from the divergence angle of light passing through the second lens surface 126 in the second direction.

[0239] The aforementioned first distance R1 and second distance R2 can correspond to the basic conditions for designing the first unit pattern 122 and the second unit pattern 126 to have arcuate shapes to collect light in the first and second directions. Therefore, in the first lens surface 121 formed by the collection of the first unit pattern 122 and the second lens surface 126 formed by the extension of the second unit pattern 126, light is collected in the first and second directions respectively to output collimated light, thereby preventing light loss due to light collection and enabling high resolution output.

[0240] In addition, the conic constant of the first lens surface 121 is -3.5874, and the conic constant of the second lens surface 126 is -0.7648, as shown in Table 2 below.

[0241] [Table 2]

[0242] As shown in the figure, since the first lens surface 121 is a collection of multiple first unit patterns 122, when only considering the aspherical coefficient used for the second lens surface 126, it is preferable to apply the aspherical coefficient so that when the aspherical coefficient is applied to the second lens surface 126, the conic constant becomes -0.7648, and it is preferable to apply the conic constant of -3.5874 to the first lens surface 121 corresponding to the second lens surface 126.

[0243] Therefore, as described above, the first lens surface 121 and the second lens surface 126 can be formed aspherical, and simultaneously, collimated light can be output in the first direction of light collected by the first lens surface 121 and the second direction of light collected by the second lens surface 126, respectively.

[0244] Therefore, the collimated light collected in the first and second directions can be output and reflected from the object without loss of light, and the reflected light is incident, thus providing the advantage of high output resolution.

[0245] Meanwhile, when the reflective bulk Bragg grating V is disposed in the LiDAR device according to an embodiment of the present invention, the light emitted by the light source 111 can pass through the second lens unit 120, be output as collimated light, and be emitted toward the reflective bulk Bragg grating V.

[0246] However, the volume Bragg grating V can transmit a portion of the light and reflect a portion of the light, and the reflected light can move along the same optical path toward the light source 111.

[0247] That is, when this situation is repeated, a light resonant structure can be formed between the light source 111 and the volume Bragg grating V.

[0248] Specifically, such as Figure 24 As shown, the light emitted by the light source 111 can be collected by the first lens surface 121 in the first direction and move towards the volume Bragg grating V as collimated light. A portion of the light can be reflected by the volume Bragg grating V, and the reflected light can move towards the light source 111 along the same optical path.

[0249] In addition, such as Figure 25 As shown, the light emitted by the light source 111 can be collected by the second lens surface 126 in the second direction and moved towards the volume Bragg grating V as collimated light. A portion of the light can be reflected by the volume Bragg grating V, and the reflected light can move towards the light source 111 along the same optical path.

[0250] Therefore, in this invention, the first lens surface 121 may include a first unit pattern 122, each first unit pattern having an arcuate shape with a first distance R1 based on a third axis 123, and a plurality of first unit patterns 122 may be arranged in a first direction to form the first lens surface 121.

[0251] Additionally, the second lens surface 126 may include a second unit pattern 127 having an arcuate shape based on the fourth axis 128 with a second distance R2, and the second unit pattern 127 may extend in the first direction to form the second lens surface 126.

[0252] Furthermore, the third axis 123, which serves as a reference for the first unit pattern 122, and the fourth axis 128, which serves as a reference for the second unit pattern 127, can be perpendicular to each other, and the direction in which the first unit pattern 122 extends and the direction in which the second unit pattern 127 extends can also be perpendicular to each other.

[0253] Meanwhile, as shown in Table 1, the LiDAR device 1000 according to an embodiment of the present invention is preferably applied to the wavelength band of 1350nm to 1450nm, that is, the light emitted by the light source 111 can be within the wavelength band of 1350nm to 1450nm.

[0254] More specifically, the wavelength band of the light emitted by the light source 111 can be from 1400 nm to 1430 nm, and based on Table 1, it is preferably 1430 nm.

[0255] Therefore, 1430nm can correspond to the wavelength band of 1.43μm, and generally falls within the wavelength band corresponding to near-infrared. Since the LiDAR device 1000 senses 3D image information about a mid-to-long object (subject) by detecting the light reflected from the object (subject), it is probably preferable to apply near-infrared light suitable for mid-to-long distance.

[0256] That is, the LiDAR device 1000 according to an embodiment of the present invention can preferably use a light source 111 that emits light in the wavelength band of 1350nm to 1450nm to increase the effect of image sensing. Specifically, the light source 111 emits light in the wavelength band of 1430nm, and the second lens unit 120 according to an embodiment of the present invention can collect light in the wavelength band of 1430nm and output the light as collimated light to improve the resolution of 3D image information of the LiDAR device 1000.

[0257] Figure 26 This is a perspective view of a LiDAR system according to an embodiment of the present invention. Figure 27 This is an exploded view of a LiDAR system according to an embodiment of the present invention, and Figure 28 This is an exploded view of a LiDAR device according to an embodiment of the present invention.

[0258] Reference Figures 26 to 28 The light emitting unit 100 and the light receiving unit 200 can be housed within the housing 50 of the LiDAR system 1200. As shown, a LiDAR system 1200 can include multiple LiDAR devices 1000. For example, each LiDAR device 1000 included in a LiDAR system 1200 includes a light emitting unit 100 and a light receiving unit 200, and two LiDAR devices 1000 can be configured to face opposite directions.

[0259] Multiple openings can be formed in the housing 50. Among the multiple openings, a first opening 51 can be configured to correspond to a window 250 of the LiDAR device 1000 and can be used as a channel for light emission and light reception. Among the multiple openings, a second opening 52 can be used as a channel for dissipating heat generated from the LiDAR device 1000 housed in the housing 50.

[0260] The number of first openings 51 may be less than the number of second openings 52, and the diameter of the first opening 51 may be greater than the diameter of the second opening 52. Since the first openings 51 are configured to correspond to the windows 250 of the LiDAR device 1000, the number of first openings 51 formed in the housing 50 may be the same as the number of LiDAR devices 1000 housed in the housing 50.

[0261] Each LiDAR device 1000 may include a light emitting unit 100 and a light receiving unit 200, and for this purpose, each LiDAR device 1000 may further include a mount 600 on which the light emitting unit 100 and the light receiving unit 200 are mounted. The light emitting unit 100 may be disposed on a side surface of the light receiving unit 200, and light emitted from the light emitting unit 100 and light reflected from an object and then incident on the light receiving unit 200 may both pass through a window 250.

[0262] Although not shown in detail, the light emitting unit may include a substrate, a light source, optical components, a shielding component, and a diffusion component. The substrate may include a printed circuit board (PCB). The substrate can be connected to a connector via a flexible printed circuit board (FPCB). The light source is disposed on the substrate, and the substrate may include terminals. The light source may correspond to the light source of the light emitting unit 100 described above. That is, the light source may include multiple emitters arranged in an array. The multiple emitters are capable of emitting light in m... The n-matrix arrangement corresponds to the pixel array of the image sensor 210 of the light receiving unit 200, but is not limited thereto. The driving of multiple emitters can be controlled individually or collectively. Optical components can collect light emitted from the light source, or can redirect the optical path of light emitted from the light source. For example, when the light source is not set to face window 250, the optical components can redirect the optical path so that light emitted from the light source is emitted through window 250. Shielding components can surround the substrate and the light source, can be referred to as a cover can, and can be made of a non-magnetic material, thus blocking electromagnetic interference (EMI) noise. Diffusion components can be diffuser lenses or homogenizers. Diffusion components can be positioned in the optical path of light emitted from the light source.

[0263] The light receiving unit 200 may include a sensor unit and a lens unit. The sensor unit may include a substrate, an image sensor 210 disposed on the substrate, and a microlens array disposed on the image sensor 210. The image sensor 210 can detect infrared light. The image sensor 210 can detect light beams of specific wavelengths within the infrared spectrum. The lens unit may include a lens barrel 260, multiple lenses, a filter, and a lens hood 270. The image sensor 210 can detect light passing through the filter. The image sensor 210 can detect light within the wavelength band of the light source. Therefore, light emitted from the light source and reflected by the subject can be detected by the image sensor 210, thereby sensing 3D image information about the subject.

[0264] As described above, the LiDAR device according to embodiments of the present invention can be a mechanical LiDAR device. Therefore, the LiDAR device according to embodiments of the present invention can be designed to rotate 360 ​​degrees by a motor.

[0265] Having examined exemplary embodiments of the invention, it will be apparent to those skilled in the art that the invention can be implemented in other specific forms without departing from the spirit or scope of the invention, in addition to the embodiments described above.

[0266] Therefore, the above embodiments should be considered exemplary and not limiting, and thus the invention is not limited to the above description, but can be modified within the scope of the appended claims and their equivalents.

Claims

1. A LiDAR (Light Detection and Ranging) device, comprising: A light emitting unit configured to emit optical signals toward an object; as well as A light receiving unit configured to receive optical signals reflected from the object. The optical receiving unit includes: An image sensor, the image sensor including a light-receiving surface having a long axis in a first direction; A first lens unit is disposed on the image sensor; A window, the window being disposed on the first lens unit; and A filter, wherein the filter is disposed between the image sensor and the window, and At least one of the filters and the window is tilted relative to the light-receiving surface of the image sensor about a virtual first axis parallel to the long axis or about a second axis tilted relative to the first axis.

2. The LiDAR device according to claim 1, wherein, The image sensor includes a pixel array arranged in a first direction and a second direction perpendicular to the first direction, wherein the number of pixels arranged in the first direction is greater than the number of pixels arranged in the second direction. At least one of the filters and the window is tilted about the first direction, which is the axis of rotation.

3. The LiDAR device according to claim 2, wherein, The filter and each of the windows are tilted about the first direction, which is the axis of rotation.

4. The LiDAR device of claim 1, further comprising a microlens array disposed between the image sensor and the first lens unit and having a long axis in the first direction. in, At least one of the filters and the window is tilted relative to the microlens array about a virtual axis parallel to the long axis of the microlens array.

5. The LiDAR device according to claim 4, wherein, The microlens array includes a plurality of microlenses arranged in the first direction and in a second direction perpendicular to the first direction, and The number of microlenses arranged in the first direction is greater than the number of microlenses arranged in the second direction.

6. The LiDAR device according to claim 1, wherein, The image sensor includes m An n-pixel array, where the ratio of m to n is 8 or greater.

7. The LiDAR device according to claim 3, wherein, The filter and one of the windows are tilted clockwise about the first direction which is the axis of rotation, and the filter and the other of the windows are tilted counterclockwise about the first direction which is the axis of rotation.

8. The LiDAR device according to claim 1, wherein, The optical emitting unit includes: Light source unit; and The second lens unit includes a first lens surface facing the light source unit and a second lens surface disposed opposite to the first lens surface. The first lens surface includes a plurality of first unit patterns arranged in the first direction, and the first unit patterns extend in a second direction perpendicular to the first direction. The second lens surface includes a second unit pattern having a long axis extending in the first direction.

9. The LiDAR device according to claim 8, wherein, The first lens surface and the second lens surface are asymmetrical relative to each other.

10. The LiDAR device according to claim 9, wherein, The first unit pattern has an arcuate shape based on an axis parallel to the second direction, and The second unit pattern has an arc shape based on an axis parallel to the first direction.

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