Electronic laser scanning device without mechanical driving unit

Abstract

The present invention relates to an electronic laser scanning device capable of electronically scanning a subject without a mechanical driving unit. The present invention relates to technology capable of precisely scanning a subject without a mechanical driving unit by precisely adjusting the polarization and reflection and refraction angles of a laser signal by using an electronic transmission / reception optical modulator and a scan lens.

Description

Electronic laser scanning device without mechanical drive parts

[0001] The present invention relates to an electronic scanning device using a laser, and more specifically, to an electronic laser scanning device capable of scanning an object by electronically polarizing, reflecting, and refracting a laser beam without a mechanical driving part. The present invention can be used to precisely detect the position, distance, and shape of an object in a non-contact sensor system such as LiDAR.

[0002]

[0003] Conventional LiDAR systems include mechanical rotation devices for omnidirectional scanning of three-dimensional space. The mechanical rotation devices used in LiDAR radiate laser beams in all directions or scan lasers reflected from objects by rotating mirrors capable of reflecting laser beams at high speeds, thereby collecting distance and shape data for objects in all directions.

[0004] However, conventional LiDARs containing mechanical rotating devices that rotate the scanner face limitations in miniaturization due to their mechanical structure, which includes various gears, motors, and rotating parts. In particular, in equipment such as autonomous vehicles or small robots where LiDAR systems are essential, the application of conventional LiDAR systems containing mechanical rotating devices has been limited due to the structural complexity and miniaturization limitations of such devices.

[0005] Furthermore, conventional lidars containing mechanical rotating devices have the disadvantage of requiring maintenance because structural damage (such as wear and tear) occurs due to the continuous operation of rotating parts. In particular, conventional lidars had the disadvantage of increasing replacement and repair costs as the failure rate of the rotating devices increases with prolonged use.

[0006] As prior art related to scanning devices that scan an object using a laser, Korean Published Patent No. 10-2019-0012345 "Lidar device" discloses a lidar device comprising a light source that generates source light and a rotating mirror whose direction of reflection surface is time-varying; Korean Published Patent No. 10-2023-0022805 "Scanning mirror-based lidar device" discloses a lidar device comprising a light source that generates a laser, a scanning mirror that changes the angle of incident light reflected back from an object to emit or collect light through unidirectional high-speed rotational scanning, and a second collimation lens; and Korean Registered Patent No. 10-1925816 "Distance calculation method and lidar device performing the same" discloses a lidar device comprising a laser output unit and a rotating multi-faceted mirror that reflects the laser at multiple angles.

[0007] The aforementioned conventional technologies disclose a structure that rotates a mirror to reflect a laser beam in multiple directions or collects subject information by receiving reflected signals from each direction. However, since such a rotary mirror method relies on the physical rotation of the mirror, it still has the problem of an increased possibility of physical damage and has limitations in terms of miniaturization and weight reduction.

[0008] The present invention was devised to solve the above-mentioned problems, and

[0009] The purpose is to solve the difficulties in miniaturization and maintenance issues arising from the reliance of conventional LiDAR systems on mechanical rotation methods.

[0010]

[0011] The present invention for achieving the above-mentioned purpose is,

[0012] An electronic laser scanning device comprises: a laser generator that generates a polarized laser beam; a transmitting light adjuster that adjusts the polarization characteristics of the polarized laser beam generated from the laser generator to a preset polarization state; a scanning lens that includes a conical upper lens and reflects the polarized laser beam received from the transmitting light adjuster at a preset angle through the reflective surface of the upper lens; a receiving lens that receives a reflected laser incident on a subject after the polarized laser beam is reflected from the subject; a receiving light adjuster that passes only the reflected laser having the same polarization characteristics as the polarized laser adjusted by the transmitting light adjuster from the reflected laser received from the receiving lens; and a receiving sensor that receives the reflected laser passed through the receiving light adjuster and measures the position and distance of the subject by analyzing the polarization state of the received reflected laser.

[0013] Additionally, in one embodiment, the laser generator comprises: a laser diode that generates a polarized laser beam; and an aspherical lens that converts the shape of the polarized laser beam into a preset shape.

[0014] In addition, in one embodiment, the laser generator includes a laser diode that generates a laser beam; and a polarizing plate that passes the laser beam generated from the laser diode and generates a polarized laser beam with preset polarization characteristics.

[0015] In addition, in one embodiment, the transmitting light adjuster includes a liquid crystal device that passes a polarized laser beam generated from the laser generator and adjusts the polarization characteristics of the polarized laser beam to a preset polarization state.

[0016] Additionally, in one embodiment, the scan lens comprises an upper lens that is positioned oppositely toward the transmitting light adjuster and is formed in a conical shape with a multilayer film reflector applied to a reflective surface, and which adjusts a polarized laser beam incident axially from the transmitting light adjuster to a preset polarization characteristic through the multilayer film reflector and reflects it at a preset angle.

[0017] Additionally, in one embodiment, the scan lens comprises: an upper lens positioned oppositely toward the transmitting light adjuster and formed in a conical shape to reflect a polarized laser beam incident axially from the transmitting light adjuster at a preset angle through a conical reflective surface; and a lower lens formed in a hollow cylindrical shape having a diameter larger than that of the upper lens and connected to the lower part of the upper lens to support the upper lens.

[0018] Additionally, in one embodiment, the scanning lens comprises an inverted conical hollow portion positioned above the upper lens to share the same central axis as the upper lens, and includes an incident light blocking region that blocks reflection and refraction at a specific angle of a polarized laser beam incident on the center of the upper lens.

[0019] In addition, in one embodiment, the scan lens further includes a lens fastening part formed on the upper edge of the lower lens and formed by a fastening groove formed inwardly corresponding to the shape of the lower part of the lower lens, and through the fastening of the lens fastening part and the lower part of the lower lens, one or more scan lenses are serially connected vertically on the same central axis.

[0020] Additionally, in one embodiment, the receiving lens comprises: a receiving lens that receives a reflected laser reflected from a subject; and a light-blocking cover that surrounds the outside of the receiving lens and includes a side slit that passes the reflected laser through the side.

[0021] In addition, in one embodiment, the receiving light adjuster includes a receiving liquid crystal that adjusts the polarization angle of the incident light; and a second polarizer that transmits only a reflected laser having the same polarization characteristics as the polarized laser adjusted in the transmitting light adjuster.

[0022] In addition, in one embodiment, the laser generator is eccentrically positioned such that its central axis is spaced in one direction from the central axis of the scan lens in the direction where the subject is located.

[0023]

[0024] Through the above configuration, the present invention provides the following advantages.

[0025] 1) By reflecting the laser beam through an electronic light adjuster and a conical scan lens, it is possible to scan objects in all directions, thereby eliminating the need for a mechanical rotating device required in conventional scanning devices. Consequently, the structure of the scanning device is simplified, which has the advantage of being able to be miniaturized and lightweight.

[0026] 2) By using a transmitting / receiving optical adjuster capable of electronically adjusting the polarization angle of a polarized laser beam, the shape and distance of an object can be detected with high precision.

[0027] 3) By configuring the omnidirectional scanning structure including the conventional mechanical rotating device as an electronic device, durability is improved compared to the physical operating structure of the mechanical rotating device. Therefore, the present invention has the advantage of enabling stable use for a long period and reducing long-term maintenance costs.

[0028]

[0029] FIG. 1 is a block diagram schematically showing the configuration of an electronic laser scanning device according to a preferred embodiment of the present invention.

[0030] FIG. 2 is a conceptual diagram illustrating a laser diode and a polarizing plate according to a preferred embodiment of the present invention.

[0031] FIG. 3 is a conceptual diagram illustrating the conversion of a laser beam through an aspherical lens according to a preferred embodiment of the present invention.

[0032] FIG. 4 is an upper perspective view (a) and a lower perspective view (b) illustrating a transmitting optical regulator according to a preferred embodiment of the present invention.

[0033] FIG. 5 is a side cross-sectional view illustrating the configuration of a scan lens to which a multilayer film reflector is applied according to an embodiment of the present invention and the reflected light of a laser beam reflected through the multilayer film reflector.

[0034] FIG. 6 is a side cross-sectional view illustrating the configuration of a scan lens according to one embodiment of the present invention and the reflection and refraction structure of a laser through the scan lens.

[0035] FIG. 7 is a conceptual diagram illustrating the objective focal length of a laser beam emitted from a scan lens according to a preferred embodiment of the present invention.

[0036] FIG. 8 is a conceptual diagram illustrating the light source focal length and objective focal length of a laser beam emitted from a scan lens according to a preferred embodiment of the present invention.

[0037] FIG. 9 is a side cross-sectional view illustrating a structure in which a plurality of scan lenses (30 to 30-3) are connected in series according to one embodiment.

[0038] FIG. 10 is a conceptual diagram illustrating the structure of a receiving lens according to a preferred embodiment of the present invention.

[0039] FIG. 11 is a conceptual diagram illustrating the structure of a receiving light adjuster and a receiving sensor according to a preferred embodiment of the present invention.

[0040] FIG. 12 is a conceptual diagram illustrating a structure in which the central axis of a laser generator according to one embodiment is eccentrically positioned in one direction from the central axis of a scan lens.

[0041] FIG. 13 is a conceptual diagram illustrating the process of detecting an object using an electronic laser scanning device according to a preferred embodiment of the present invention.

[0042] FIG. 14 is a conceptual diagram illustrating the subject detection process of an embodiment in which subject scanning is performed simultaneously in each of the two electronic scanning devices (LSS1 and LSS2).

[0043] FIG. 15 is a conceptual diagram illustrating the process of detecting a subject in an embodiment in which a polarized laser is transmitted from one of two electronic scanning devices (LSS1 and LSS2) and a reflected laser is received from the other.

[0044]

[0045] Preferred embodiments that can be easily practiced by those skilled in the art to which the present invention pertains are described in detail below with reference to the attached drawings. However, in describing the operating principles of the preferred embodiments of the present invention in detail, if it is determined that a specific description of related known functions or configurations may unnecessarily obscure the essence of the present invention, such detailed description is omitted. This is intended to convey the core of the present invention more clearly without obscuring it by omitting unnecessary descriptions. Furthermore, since the present invention is susceptible to various modifications and may have various embodiments, specific embodiments are illustrated in the drawings and described in detail in the detailed description; however, this is not intended to limit the present invention to specific embodiments, and it should be understood that it includes all modifications, equivalents, and substitutions that fall within the spirit and technical scope of the present invention.

[0046]

[0047] The present invention relates to an electronic laser scanning device capable of omnidirectional scanning electronically without a mechanical drive unit. The present invention aims to solve the difficulties in miniaturization and maintenance issues arising from the reliance on mechanical rotation methods of existing LiDAR systems. It discloses a device comprising an electronic transmitting / receiving optical adjuster and a scanning lens, which can precisely scan an object without a mechanical drive unit by adjusting the polarization, reflection, and refraction angles of a laser signal.

[0048] More specifically, the present invention comprises a laser generator, a transmitting light adjuster, a scanning lens, a receiving lens, a receiving light adjuster, and a receiving sensor. The laser generator generates a polarized laser beam used for scanning a subject and adjusts the polarization characteristics of the polarized laser beam through the transmitting light adjuster. The scanning lens reflects and refracts the polarized laser beam and radiates it toward the subject, and transmits the reflected laser incident from the subject, which is reflected through the receiving lens and the receiving light adjuster, to a receiving sensor after filtering for noise and polarization. The receiving sensor analyzes the received reflected laser to perform scanning of the subject using the polarized laser.

[0049]

[0050] Hereinafter, the detailed configuration of an electronic laser scanning device according to a preferred embodiment of the present invention will be described in detail with reference to the drawings.

[0051] FIG. 1 schematically shows the configuration of an electronic laser scanning device according to a preferred embodiment of the present invention, FIG. 2 shows a laser diode and a polarizing plate according to a preferred embodiment of the present invention, and FIG. 3 shows the conversion of a laser beam through an aspherical lens according to a preferred embodiment of the present invention.

[0052] Additionally, FIG. 4 illustrates a transmitting light adjuster according to a preferred embodiment of the present invention, FIG. 5 illustrates the configuration of a scan lens to which a multilayer film reflector is applied according to one embodiment of the present invention and the reflected light of a laser beam reflected through the multilayer film reflector, FIG. 6 illustrates the configuration of a scan lens according to a preferred embodiment of the present invention and the reflection and refraction structure of a laser through the scan lens, and FIG. 7 illustrates the objective focal length of a laser beam emitted from a scan lens according to a preferred embodiment of the present invention.

[0053] Additionally, FIG. 8 illustrates the light source focal length and objective focal length of a laser beam emitted from a scan lens according to a preferred embodiment of the present invention, FIG. 9 illustrates a structure in which a plurality of scan lenses (30 to 30-3) are connected in series according to one embodiment, FIG. 10 illustrates the structure of a receiving lens according to a preferred embodiment of the present invention, FIG. 11 illustrates the structure of a receiving light adjuster and a receiving sensor according to a preferred embodiment of the present invention, and FIG. 12 illustrates a structure in which the central axis of a laser generator according to one embodiment is eccentrically positioned in one direction from the central axis of the scan lens.

[0054] Additionally, FIG. 13 illustrates a subject detection process using an electronic laser scanning device according to a preferred embodiment of the present invention, FIG. 14 illustrates a subject detection process of an embodiment in which a subject scan is performed simultaneously at each of two electronic scanning devices (LSS1 and LSS2), FIG. 14 illustrates a subject detection process of an embodiment in which a polarized laser is transmitted from one of the two electronic scanning devices (LSS1 and LSS2) and a reflected laser is received from the other.

[0055]

[0056] 1. Laser generator (10)

[0057] 1) Laser diode (11)

[0058] In a preferred embodiment of the present invention, the laser generator (10) includes a laser diode (11) that generates a laser beam. More preferably, the laser diode (11) includes a polarized laser diode that generates a polarized laser beam, and the polarized laser beam generated through the polarized laser diode (11) is provided to a transmitting light adjuster (20) and a scan lens (30) to be described later.

[0059] However, the laser diode (11) of the present invention is not limited to embodiments including the polarized laser diode described above. In one embodiment, the laser diode (11) may include an unpolarized laser diode that generates an unpolarized laser that does not have polarization characteristics. In this embodiment, a polarizer (12) additionally configured to polarize the unpolarized laser beam generated through the unpolarized laser diode may be further included.

[0060]

[0061] The laser diode (11) may include all known laser light sources applicable to a LiDAR device in which a subject is scanned using a laser. For example, the laser diode (11) may include one of a near-infrared (NIR) laser diode with a wavelength range of 905 nm, a mid-infrared (MIR) laser diode with a wavelength range of 1550 nm, a VCSEL (Vertical Cavity Surface Emitting Laser) diode, and a DFB (Distributed Feedback) laser diode.

[0062] However, the laser diode (11) of the present invention is not limited to one of the laser diodes listed above, and should be understood to include all known laser diodes applicable in the field of laser scanning devices intended for scanning a subject, as well as all types of laser light sources developed in the future for application in the same technical field.

[0063]

[0064] 2) Polarizing plate (12)

[0065] As described above, the laser diode (11) of a preferred embodiment of the present invention includes a polarizing laser diode that generates a polarized laser beam having polarization characteristics, but the laser diode of one embodiment includes an unpolarized laser diode that generates an unpolarized laser beam that does not have polarization characteristics.

[0066] Accordingly, the laser generator (10) can impart polarization characteristics to the laser beam by placing a polarizing plate (12) in the direction of irradiation of the unpolarized laser beam generated from the laser diode (11). The polarizing plate (12) may include all known polarizing plates capable of adding polarization characteristics to a light source, but is not limited thereto.

[0067] The polarizing plate (12) can generate a polarized laser by adding polarization characteristics to an unpolarized laser beam generated from the laser diode (11). More specifically, the polarizing plate (12) can generate a polarized laser beam by imparting polarization characteristics to an unpolarized laser beam passing through the polarizing plate (12) by allowing only the specific directional vibration components of the laser to pass through and blocking the rest.

[0068] In one embodiment, the polarizing plate (12) includes a polymer film polarizer. The polymer film polarizer is lightweight and can control polarization with high efficiency, making it suitable for miniaturizing and reducing the weight of a scanning device.

[0069] The polarizing plate (12) is positioned in front of the irradiation direction of the laser beam generated from the laser generator (10), suppresses unnecessary polarization components of the incident laser beam, and allows only polarization components of a specific direction (e.g., vertical direction) to pass through. Through such polarization adjustment, the unpolarized laser beam irradiated from the laser generator (10) is polarized before being projected onto the scan lens (30), and thus, a laser beam having polarization characteristics can be irradiated onto the scan lens (30).

[0070]

[0071] 3) Aspherical lens (13)

[0072] The above-described aspherical lens (13) converts the laser beam emitted in the form of an elliptical beam from the laser diode (11) into a circular beam, thereby changing the shape of the laser beam so that a circular laser beam with a constant light flux density is incident on the scan lens (30). Adjusting the shape of the laser beam through the above-described aspherical lens (13) improves scanning precision and minimizes beam distortion that may occur as the scanning angle changes.

[0073] The above-described aspherical lens (13) is designed in an aspherical shape with an inconsistent radius of curvature, and is optimized to convert an elliptical laser beam into a uniform circular laser beam. Such an optical structure minimizes scattering of the beam generated from the laser diode (11) and controls the path of the beam passing through the scan lens (30) to transmit it in the correct direction. In other words, the radius of curvature of the aspherical lens (13) is set to correct the elliptical shape of the incident beam and convert it into a circle.

[0074] As shown in FIG. 3, the aspherical lens (13) performs the function of converting the shape of the beam into a circle when an elliptical beam generated from the laser generator (10) is incident.

[0075] Generally, the shape of the laser beam generated and emitted from a laser diode is elliptical. Such an elliptical laser beam has a non-uniform light distribution and divergence angle. Therefore, the electronic laser scanning device of the present invention further includes an aspherical lens (13) that adjusts the shape of the laser beam to a circular shape in order to increase accurate scanning accuracy.

[0076] The curvature of the aspherical surface of the aspherical lens (13) changes the angle of incidence of the incident laser beam to correct a specific part of the beam, and consequently forms a uniform circular laser beam. In a preferred embodiment of the present invention, the aspherical lens (13) may be made of a material that provides high optical transmittance and durability. In one embodiment, the aspherical lens (13) may be made of optical glass or plastic resin.

[0077]

[0078] Meanwhile, the laser generator (10) of a preferred embodiment of the present invention has its central axis positioned on the same axis as the central axis (Lc in FIG. 6) of the scan lens (30) to be described later. Accordingly, a circular laser beam emitted from the laser generator (10) is incident axially in a circular manner from the center of the scan lens (30).

[0079] In one embodiment, the central axis of the laser generator (10) is eccentrically positioned in one direction from the central axis of the scan lens (30) toward the direction in which the subject is located. FIG. 12 illustrates an embodiment in which the central axis of the laser generator (10) is eccentrically positioned from the central axis of the scan lens (30) in this manner. In this embodiment, the light source central axis (LD) of the laser generator (10)C ) is eccentrically positioned in one direction (the right direction in FIG. 12) from the center axis of the scan lens (30), that is, toward the scan target range (the direction in which the subject is located). Through this structure, the transmission light efficiency of the laser beam for scanning the subject can be further increased.

[0080] In addition, in this embodiment, the aspherical lens (13) is eccentrically positioned at the center axis of the light source (LD) that is the shape of the polarized laser beam. C By setting the curvature to convert into a shape corresponding to (e.g., the cut donut shape shown in FIG. 12), the light flux density of the polarized laser beam can be adjusted to be constant. Through such a configuration, the transmission light efficiency through the scan lens (30) can be greatly increased.

[0081]

[0082] 2. Transmitting optical regulator (20)

[0083] The transmitting light adjuster (20) of the present invention adjusts the polarization characteristics of a polarized laser beam generated from the laser generator (10) to a preset polarization state suitable for scanning a subject. The transmitting light adjuster (20) may include a known liquid crystal device (hereinafter, transmitting liquid crystal) capable of adjusting the polarization state of an incident laser.

[0084] The above-mentioned transmitting liquid crystal adjusts the voltage within the transmitting light adjuster (20) to rotate and adjust the polarization angle of the laser beam incident on one side (the upper surface of the transmitting liquid crystal in FIG. 4(a)) and passes it to the other side (the lower surface of the transmitting liquid crystal in FIG. 4(b). When the polarized laser beam passes through the transmitting liquid crystal, the polarization angle of the laser beam changes according to the voltage applied to the transmitting liquid crystal, and through this, the polarization angle of the laser beam irradiated onto the scanning lens (30) can be adjusted to have a preset polarization characteristic. In this way, the transmitting liquid crystal can finely adjust the polarization characteristics of the polarized laser through precise voltage control, and high-precision scanning of the subject is possible through the polarized laser with such finely adjusted characteristics.

[0085]

[0086]

[0087] 3. Scan lens (30)

[0088] The above-described scan lens (30) reflects a polarized laser beam, generated from the laser generator (10) and having its polarization characteristics adjusted through the transmitting light adjuster (20), toward a scan target range (including the position of the subject) at a preset angle. At this time, the scan lens (30) includes an upper lens formed in a conical shape, and the reflection of the polarized laser beam reflected from the surface (reflective surface) of the conical lens results in directional reflection due to the S-polarization characteristics of the polarized laser. Such directional reflection of the polarized laser beam can be explained in a manner similar to the principle in which a light beam concentrated from a light source located at the focal point of a reflective mirror in a searchlight of a lighthouse is reflected with directionality to a distant area.

[0089]

[0090] In a preferred embodiment of the present invention, the scan lens (30) includes an upper lens (31) and a lower lens (32), and implements a precise and consistent omnidirectional scan through the reflection and refraction of a laser beam.

[0091]

[0092] 1) Upper lens (31)

[0093] The upper lens (31) is formed in a conical shape and is steered toward the transmitting light adjuster (20) to reflect and refract the incident polarized laser beam passing through the transmitting light adjuster (20) and radiate it. By reflecting the polarized laser beam with directionality, the upper lens (31) enables precise scanning of the target scanning area.

[0094] In a preferred embodiment of the present invention, the upper lens may include a transparent optical lens or a metal lens to which a multilayer reflector is applied.

[0095]

[0096] 1) An example in which the upper lens comprises a metal lens having a multilayer reflector applied thereto

[0097] In an embodiment where the upper lens (31) comprises a metal lens with a multilayer reflector applied thereto, the upper lens (31) comprises a multilayer reflector applied to its surface, and a laser beam incident on the upper lens (31) is adjusted to a preset polarization characteristic through the multilayer reflector and then reflected in all directions. FIG. 5 illustrates in detail the reflected light of the laser beam reflected through the multilayer reflector in this manner.

[0098] Generally, multilayer mirrors have a structure in which high-refractive-index and low-refractive-index layers are alternately stacked, and depending on the angle of incidence and the structure of the multilayer film (coating), they produce different reflectances and phase changes according to the polarization state.

[0099] In other words, the above-described multilayer reflector can be configured to create different reflection phase differences for S-polarized and P-polarized light, and to reflect the polarized light by rotating it (λ / 2) or converting it into circularly polarized light (λ / 4) using this phase difference.

[0100] Accordingly, the upper lens (31) with the above-mentioned multilayer film reflector applied to its surface can be designed so that the S / P phase difference Δφ is maintained almost constant through the above-mentioned multilayer film design of the reflective surface, or can be configured to reflect by adjusting the polarization characteristics of the incident laser beam to create a phase difference corresponding to λ / 2 or λ / 4 at a specific angle.

[0101] In a preferred embodiment of the present invention, the upper lens (31) is formed in a conical shape having an inclined surface at a 45° angle, and a vacuum-deposited multilayer film reflector is applied to the reflective surface. However, it should be noted that this is merely a preferred embodiment of the present invention, and that a different reflective surface angle and a different type of multilayer film reflector may be applied as needed.

[0102]

[0103] 2) An example in which the upper lens includes a transparent optical lens

[0104] In an embodiment in which the upper lens (31) includes a transparent optical lens, a laser beam incident on the upper lens may be partially refracted inward and transmitted downward along with omnidirectional radiation through reflection. FIG. 6 illustrates in detail the reflected light, refracted light, and transmitted light of such a laser beam. In this way, the refracted light and transmitted light refracted inward through the upper lens (31) can be re-radiated through a scan lens (30-1 to 30-3 in FIG. 9) connected in series with the upper lens (31) to increase scanning efficiency, and the details thereof will be described later.

[0105]

[0106] Meanwhile, a conical hollow portion is formed at the bottom of the upper lens (31). Through the shape of the hollow portion of the upper lens (31), refracted light passing through the upper lens (31) can be transmitted and proceed in one direction (inward downward direction in FIG. 6). The direction of propagation of the transmitted light can be determined from the shape of the hollow portion.

[0107]

[0108] 2) Lower lens (32)

[0109] The lower lens (32) is formed in a hollow cylindrical shape and is connected to the lower part of the upper lens (31) to provide a structural function of supporting the upper lens (31). Additionally, a plurality of scan lenses (30) can be stacked and connected in series through the lower lens (32). The lower lens (32) shares the same central axis as the upper lens (31), and the upper lens (31) is positioned at an objective focus height (L in FIG. 8) so that the laser beam (Laser 4 in FIG. 6) reflected through the upper lens (31) is transmitted to the subject to be scanned. H It functions to support the position of ).

[0110] In one embodiment, a plurality of scan lenses (30) are stacked vertically and connected in series through the lower lens (32). FIG. 9 illustrates an embodiment in which four scan lenses (30 to 30-3) are stacked vertically and connected in series. Through the scan lenses (30 to 30-3) connected in series in this manner, transmitted light that is refracted and propagates toward the inner side of the uppermost scan lens (30) passes through the lower lens and is re-radiated through the lower scan lenses (30-1 to 30-3), thereby increasing scanning efficiency.

[0111]

[0112] 3) Lens fastening part (33)

[0113] The lens fastening portion (33) is a groove formed on the upper edge of the lower lens (32), through which the scanning lens is stacked. More specifically, the lens fastening portion (33) includes a groove formed in a shape corresponding to the shape of the lower part of the lower lens (32). Accordingly, through the groove of the lens fastening portion (33), another scanning lens (30) is precisely coupled to the upper part of any scanning lens (30), thereby ensuring the structural stability of the scanning lens (30). As a result, a plurality of scanning lenses (30) stacked and serially connected through the lens fastening portion (33) can precisely maintain the objective focus (FO of FIG. 9) of the subject to be scanned, thereby enabling the electronic laser scanning device of the present invention to maintain consistent performance in various environments.

[0114]

[0115] 4) Incident light blocking area (34)

[0116] The incident light blocking area (34) is an inverted cone-shaped hollow portion located at the central axis of the upper lens (31), and is formed to block unnecessary reflection and refraction of the laser beam incident on the upper lens (31), thereby blocking the generation of noise light that may occur during the scanning process. As shown in FIG. 6, the incident light blocking area (34) is formed to share the same central axis as the scanning lens (30), and the laser beam incident on the incident light blocking area (34) travels in a direction that does not reflect off the subject through reflection and refraction and does not enter the receiving lens (40) described later, thereby blocking the generation of noise light. Therefore, by reducing the noise of the laser beam through the incident light blocking area (34), the accuracy of the scan can be increased.

[0117]

[0118] In a preferred embodiment of the present invention, the reflection of the polarized laser beam through the scan lens (30) is directionally reflected by the upper lens (31) which is formed in a conical shape. This allows the reflected light of the polarized laser beam, reflected toward the subject to be scanned, to be concentrated so that it converges on the subject, thereby enabling precise scanning. In this directional reflection structure through the scan lens (30), as shown in FIGS. 7 and 8, the polarized laser beam reflected through the scan lens (30) is at an objective focal length (L F It was illustrated in detail through a structure that converges to ).

[0119] The directional reflection of the polarized laser beam through the upper lens (31), which is shaped like a cone as described above, can be explained in more detail through optical principles such as the Fresnel equation and the Brewster angle.

[0120] Fresnel equations refer to equations used to quantitatively calculate the reflectance and transmittance for each polarization component (S-polarization and P-polarization) when light is reflected or transmitted at the boundary between two different media. Furthermore, the aforementioned S-polarization and P-polarization are classified as S-polarization (perpendicular to the plane of incidence) and P-polarization (parallel to the plane of incidence) depending on the direction of vibration of the electric field of light, and the reflectance and transmittance for each polarization component are calculated differently through the Fresnel equations.

[0121] Brewster's angle (polarization angle) refers to the angle at which, when polarized light is incident at a specific angle of incidence, internal refraction occurs without reflection at the boundary surface due to the polarization state parallel to the plane of incidence (P-polarization).

[0122] Incident light incident at the above Brewster angle reflects only S-polarized light (approximately 15%) and does not reflect P-polarized light. Therefore, if the angle of incidence of the polarized laser beam incident on the reflective surface of the upper lens (31) of the scan lens (30) is set to be adjacent to the Brewster angle, directional reflection can be achieved in which the S-polarized light of the reflected light is maximized and the P-polarized light is minimized.

[0123] In addition, the transmitted light that is refracted and transmitted into the inner side of the upper lens (31) by setting the incident angle of the polarized laser beam as described above can be re-reflected and utilized through an optical structure in which two or more scan lenses are connected in series, as in the embodiment shown in FIG. 9 (an embodiment in which four scan lenses (30 to 30-3) are stacked vertically and connected in series), and thus, the utilization efficiency of the polarized laser beam can be greatly increased.

[0124]

[0125] Accordingly, another scan lens (30) can be precisely coupled to the upper part of any scan lens (30) through the groove of the lens fastening part (33), thereby ensuring the structural stability of the scan lens (30). As a result, a plurality of scan lenses (30) stacked and serially connected through the lens fastening part (33) can precisely maintain the objective focus (FO of FIG. 9) of the subject to be scanned, thereby enabling the electronic laser scanning device of the present invention to maintain consistent performance in various environments.

[0126] The connection structure of such a plurality of scan lenses is as shown in FIG. 10, θ0 RL and dθ0 RL = θ0 RL - θ0 RL1 The maximum number of serial connections that converge to the objective focus (FO) can be determined through the design.

[0127] In addition, since the bottom scan lens (30-3) in the structure shown in FIG. 9 does not consider the use of inner refracted light, a structure that increases the total amount of reflected light by using a metal lens that undergoes total reflection through a reflective surface can be considered.

[0128]

[0129]

[0130] 4. Receiving lens (40)

[0131] The receiving lens (40) receives a reflected laser reflected from a subject to be scanned and transmits it to a receiving light adjuster (50) to be described later. In a preferred embodiment of the present invention, the receiving lens (40) includes a light receiving lens (41) having a wide field of view to receive a reflected laser reflected from a subject and a light blocking cover (42) that attenuates noise of the reflected laser.

[0132]

[0133] 1) Light receiving lens (41)

[0134] The light-receiving lens (41) of the receiving lens (40) provides a wide field of view and serves to receive laser signals reflected from the subject at various angles. In a preferred embodiment of the present invention, the light-receiving lens (41) includes a fisheye lens. The wide field of view of the fisheye lens allows the laser beam emitted in all directions from the scanning lens (30) to effectively receive reflected lasers that are reflected from all positions of the subject. Although the light-receiving lens (41) in a preferred embodiment of the present invention is described as including a fisheye lens, it should be understood that it is not limited thereto and may include any optical device or optical mechanism of other shapes and structures for receiving lasers reflected from the subject.

[0135] The reflected laser received from the light receiving lens (41) has its direction of travel refracted through the light receiving lens (41) toward the receiving light adjuster (50) to be described later, and is supplied to the receiving light adjuster (50).

[0136]

[0137] 2) Light shield cover (42)

[0138] The light-blocking cover (42) serves to attenuate noise from the reflected laser incident on the subject. The light-blocking cover (42) is configured to block unnecessary external light or noise signals and to receive only the laser signal reflected from the subject.

[0139] In a preferred embodiment of the present invention, the light-blocking cover (42) is formed in a cylindrical shape and is configured to surround the entire light-receiving lens (41), and performs the function of blocking unnecessary light or reflected lasers entering from the outside through a side slit formed on its side. The light-blocking cover (42) can increase the measurement accuracy of the subject by blocking external light sources (noise light) unnecessary for the measurement of the subject from entering the light-receiving lens (41), in addition to the reflected laser incident from the subject.

[0140] The position and size of the above-mentioned side slit are optimized to selectively receive only the reflected laser from the subject, thereby blocking the incidence of noise light unnecessary for measurement and setting it to maximize the signal-to-noise ratio (S / N) of the reflected laser.

[0141] It is preferable that the light-blocking cover (42) be made of an opaque material or composed of a light-absorbing material so that light (including reflected laser) is not scattered from the inside or outside. As a result, the generation of noise light that may be generated by light scattering from the inside or outside of the light-blocking cover (42) can be limited.

[0142]

[0143] 5. Receiver optical adjuster (50)

[0144] The receiving light adjuster (50) filters the incident light, including the reflected laser received from the receiving lens (40), by passing only the reflected laser having the same polarization characteristics as the polarization state adjusted by the transmitting light adjuster, so that only the reflected laser usable for measuring a subject within the scan target range can be transmitted to the receiving sensor (60) to be described later.

[0145] In a preferred embodiment of the present invention, the receiving light adjuster (50) is formed with a structure corresponding to the transmitting liquid crystal of the transmitting light adjuster (20) and includes a receiving liquid crystal (51) that rotates and adjusts the polarization angle of all incident light rays, and a second polarizing plate (52) that transmits only the component of the set polarization angle (the polarization angle component identical to Laser 1 in FIG. 1, i.e., the reflected laser originating from Laser 1 among the receiving light) among the light rays passing through the receiving light adjuster (50). Accordingly, among the light rays passing through the receiving light adjuster (50), only the reflected laser having the polarization characteristics of the set polarization angle component can pass through the receiving light adjuster (50).

[0146] More preferably, the receiving liquid crystal (51) may include the same liquid crystal device as the transmitting liquid crystal used in the transmitting light adjuster (20).

[0147] The polarization angle component of the reflected laser passing through the receiving light adjuster (50) has the same polarization characteristics as the polarized laser beam (Laser0) that passes through the transmitting light adjuster (20) and is adjusted to a preset polarization angle. Therefore, only the reflected laser having the same polarization characteristics as the polarized laser beam reflected toward the subject through the scan lens (30) passes through the receiving light adjuster (50) and is used for measuring the subject.

[0148] As a result, the receiving light adjuster (50) can filter out noise light that is unnecessary for subject measurement from incident light, including a reflected laser, received through the scan lens (40), thereby greatly improving the accuracy of subject measurement within the scan target range.

[0149]

[0150]

[0151] 6. Receiver sensor (60)

[0152] The receiving sensor (60) receives the reflected laser that has passed through the receiving light adjuster (50) and analyzes the received reflected laser to measure the position and distance of the subject. More specifically, the receiving sensor (60) analyzes the reflected laser received through the receiving light adjuster (50) and calculates information regarding the distance and position of the subject. In a preferred embodiment of the present invention, the receiving sensor (60) includes a laser receiving sensor and a signal processing module.

[0153]

[0154] 1) Laser receiving sensor (not shown)

[0155] The laser receiving sensor is a device that detects a reflected laser incident through the receiving light adjuster (50).

[0156] In a preferred embodiment of the present invention, the laser receiving sensor is equipped with a high-sensitivity photodiode so as to efficiently detect even low-intensity laser signals. The high-sensitivity photodiode provides a fast response speed and high reliability, and can receive minute reflected lasers reflected from an object, thereby enabling precise measurement of the intensity and position information of the reflected lasers.

[0157] In addition, the laser receiving sensor measures the time it takes for the received laser signal to be reflected by the subject and reach it. By calculating the round-trip time of the received signal, the distance to the subject can be calculated with high precision.

[0158]

[0159] 2) Signal processing module (not shown)

[0160] The signal processing module analyzes the laser signal detected by the laser receiving sensor and obtains information such as the distance, position, and shape of the subject using a preset algorithm. In a preferred embodiment of the present invention, the signal processing module may further include a signal amplifier, a filter circuit, an arrival time calculation module, and a signal analysis and data conversion module.

[0161] The signal processing module converts the laser signal received through the laser receiving sensor into practical information, such as the distance, position, and shape of the subject. This data can ultimately be stored by the system or transmitted in real time to be provided to the user.

[0162] In a preferred embodiment of the present invention, the signal processing module analyzes the intensity, polarization, and reception time of a laser signal to calculate the position and distance of a scanned object with high precision, and analyzes and converts the calculated data in real time to generate final data.

[0163]

[0164] Meanwhile, in the process of detecting an object using the above-mentioned electronic laser scanning device, one electronic laser scanning device is sufficient for detecting an object within a general scanning range. However, for more precise object detection, two electronic laser scanning devices may be spaced apart at a predetermined distance, and more precise object detection can be achieved through bidirectional scanning of each device.

[0165]

[0166] Hereinafter, with reference to FIG. 13, a process of detecting an object using one electronic laser scanning device according to a preferred embodiment of the present invention is described.

[0167] a1) First, through the transmitting optical adjuster (20) and the receiving optical adjuster (50), the transmitting scan angle (Ф) S ) and reception scan angle (Ф R ) are in the same state Ф S and Ф R A step of varying (increasing) is carried out.

[0168] a2) Afterwards, the receiving sensor (60) sets the scan angle at the time when a subject is detected within the scan target range through the above steps as the reference angle (0), and the distance R at that time TOF Find .

[0169] a3) Afterwards, Ф in the same state S and Ф R Ф, the amount of increase or decrease in scan angle at the point where the detected subject disappears as is continuously increased RPN Get .

[0170] a4) The signal processing module of the receiving sensor (60) described above is the aforementioned central angle Ф RPN , radius R TOF In arc and the lens center (L C Point objects within the scan target range can be detected based on a straight line segment from the perspective of the viewpoint.

[0171]

[0172] Hereinafter, with reference to FIGS. 14 and 15, the process of detecting an object through each embodiment equipped with two electronic laser scanning devices is described.

[0173] FIG. 14 illustrates an embodiment in which a subject is scanned simultaneously in each of two electronic scanning devices (LSS1 and LSS2), and the coordinates of the subject can be accurately calculated using triangulation through the following steps.

[0174] b1) First, LSS1 and LSS2 are spaced at a predetermined distance (L LSS Install with a gap of ).

[0175] b2) R individually in the above LSS1 and LSS2 TOF1 and R TOF2 Find .

[0176] b3) The locations of the above LSS1 and LSS2 and the above R TOF1 and R TOF2 Calculate the accurate coordinates of the subject using triangulation.

[0177]

[0178] FIG. 15 illustrates an embodiment in which a polarizing laser is transmitted from one of two electronic scanning devices (LSS1 and LSS2) and a reflected laser is received from the other, and the coordinates of the subject can be accurately calculated through the following steps.

[0179] c1) First, LSS1 and LSS2 are spaced at a predetermined distance (L LSS Install with a gap of ).

[0180] c2) Using the method described above in LSS1, R TOF1 Find .

[0181] c3) The above LSS2 receives the reflected laser transmitted from the above LSS1 and reflected without transmitting a laser, and through this, R TOF TOTAL = R TOF1 + R TOF2 Find .

[0182] c4) R TOF1 Calculate the coordinates of the subject from the intersection point of the arc of the ellipse and LSS1 and LSS2, which are the two foci.

[0183] c5) Swap the functions of LSS1 and LSS2 to perform steps c2 through c4 above, and verify the coordinates of the subject calculated in step c4 above.

[0184]

[0185] In relation to FIGS. 14 and 15, the subject to be detected through the steps described above is assumed to be a point subject. However, the detection target of the electronic laser scanning device of the present invention is not limited to a point subject, and it should be understood that detection of a linear subject is also possible by extending the algorithm including the steps described above (b1 to b3 and c1 to c5) to a linear subject.

[0186]

[0187] For the above, the configuration of the electronic laser scanning device without a mechanical drive unit according to the present invention has been described in detail through preferred embodiments.

[0188] Through the above configuration, the present invention provides the advantage of detecting the position, distance, and shape of an object with high precision by radiating a laser beam at various angles using an electronic scanning device that is free from the mechanical rotating mechanism of the prior art. Since the present invention does not require a mechanical rotating mechanism, it offers the advantage of enabling the miniaturization and weight reduction of the device. Furthermore, by electronically adjusting the polarization angle and beam direction, it provides stable performance even in environments requiring real-time response. Moreover, since the present invention does not require mechanical rotating parts, maintenance costs are reduced, and it offers the advantage of stable operation over a long period. Consequently, the present invention can be utilized in various application fields as a high-performance scanning system equipped with precision, stability, and flexibility.

[0189]

[0190] It should be understood that the embodiments of the invention described in this specification and the configurations illustrated in the drawings relate to preferred embodiments of the invention and do not encompass all technical concepts of the invention, and that various equivalents and modifications that can replace them may exist at the time of filing. Accordingly, the invention is not limited to the embodiments described above, and any person skilled in the art to which the invention belongs can make various modifications without departing from the gist of the invention claimed in the claims, and such modifications fall within the scope of rights described in the claims of the invention.

[0191]

[0192] (Explanation of symbols)

[0193] 10: Laser generator

[0194] 11: Laser diode

[0195] 12: Polarizing plate

[0196] 13: Aspherical lens

[0197] 20: Transmitting optical regulator

[0198] 30: Scan Lens

[0199] 31: Upper lens

[0200] 32: Lower lens

[0201] 33: Lens mounting part

[0202] 34: Incident light blocking area

[0203] 40: Receiving lens

[0204] 41: Light-receiving lens

[0205] 42: Sunshade cover

[0206] 50: Receiver optical adjuster

[0207] 51: Receiver LCD

[0208] 52: Second polarizer

[0209] 60: Receiver sensor

Claims

1. In an electronic laser scanning device, Laser generator that generates a polarized laser beam; A transmitting optical adjuster that adjusts the polarization characteristics of a polarized laser beam generated from the above laser generator to a preset polarization state; A scan lens comprising a cone-shaped upper lens and reflecting a polarized laser beam received from the transmitting light adjuster at a preset angle through the reflective surface of the upper lens; A receiving lens that receives a reflected laser beam incident on a subject after the above-mentioned polarized laser beam is reflected; A receiving optical adjuster that passes only the reflected laser having the same polarization characteristics as the polarization laser adjusted in the transmitting optical adjuster from the reflected laser received from the receiving lens; and A receiving sensor that receives a reflected laser passing through the receiving light adjuster and analyzes the polarization state of the received reflected laser to measure the position and distance of the subject; including, Electronic laser scanning device.

2. In Paragraph 1, The above laser generator is, A laser diode that generates a polarized laser beam; and An aspherical lens that converts the shape of the above-mentioned polarized laser beam into a preset shape; including, Electronic laser scanning device.

3. In Paragraph 1, The above laser generator is, A laser diode that generates a laser beam; and A polarizing plate that passes a laser beam generated from the above-mentioned laser diode and generates a polarized laser beam with preset polarization characteristics; including, Electronic laser scanning device.

4. In Paragraph 1, The above-mentioned transmitting optical adjuster is, A transmitting liquid crystal that penetrates a polarized laser beam generated from the above laser generator and adjusts the polarization angle of the laser beam to have preset polarization characteristics; including, Electronic laser scanning device.

5. In Paragraph 1, The above-mentioned scanning lens is, An upper lens positioned opposite to the transmitting light adjuster and formed in a conical shape with a multilayer film reflector applied to a reflective surface, which adjusts a polarized laser beam incident axially from the transmitting light adjuster to a preset polarization characteristic through the multilayer film reflector and reflects it at a preset angle; including, Electronic laser scanning device.

6. In Paragraph 1, The above-mentioned scanning lens is, An upper lens positioned opposite to the transmitting optical adjuster and formed in a conical shape to reflect a polarized laser beam incident axially from the transmitting optical adjuster at a preset angle through a conical reflective surface; and A lower lens having a hollow cylindrical shape with a diameter larger than that of the upper lens, connected to the lower part of the upper lens to support the upper lens; including, Electronic laser scanning device.

7. In either Paragraph 5 or Paragraph 6, The above-mentioned scanning lens is, An incident light blocking region comprising an inverted conical hollow portion positioned at the upper part of the upper lens to share the same central axis as the upper part, which blocks reflection and refraction at a specific angle of a polarized laser beam incident on the center of the upper lens; including, Electronic laser scanning device.

8. In Paragraph 6, The above-mentioned scanning lens is, A lens fastening part formed on the upper edge of the lower lens and having a fastening groove formed inwardly corresponding to the shape of the lower end of the lower lens; Includes more, One or more scan lenses are serially connected vertically on the same central axis through the connection of the lens fastening part and the lower part of the lower lens, Electronic laser scanning device.

9. In Paragraph 1, The above receiving lens is, A light-receiving lens that receives a reflected laser reflected from a subject; and A light-blocking cover that surrounds the outside of the light-receiving lens and includes a side slit that passes a reflected laser through the side; including, Electronic laser scanning device.

10. In Paragraph 1, The above-mentioned receiving optical adjuster is, A receiving liquid crystal that adjusts the polarization angle of incident light; and A second polarizer that transmits only a reflected laser having the same polarization characteristics as the polarized laser adjusted in the above-mentioned transmitting optical adjuster; including, Electronic laser scanning device.

11. In Paragraph 1, The above laser generator is, The central axis is eccentrically positioned so as to be spaced in one direction from the central axis of the scan lens in the direction where the subject is located. Electronic laser scanning device.

Images