Search

EP-4737971-A1 - OPTICAL TRANSMISSION SYSTEM, OPTICAL RECEPTION SYSTEM, SENSOR SYSTEM, AND LIDAR DEVICE

EP4737971A1EP 4737971 A1EP4737971 A1EP 4737971A1EP-4737971-A1

Abstract

A receiving optical system disclosed in an embodiment of the invention includes first to fifth lenses aligned along an optical axis from an object toward a sensing unit; and an optical filter spaced apart from the sensing unit and disposed between the third lens and the fourth lens, wherein the first to fifth lenses include aspherical lenses and spherical lenses having a number of lenses greater than the number of aspherical lenses, an optical axis distance from the optical filter to a surface of the sensing unit is D1, an optical axis distance from a sensor-side surface of the fifth lens closest to the sensing unit to a surface of the sensing unit is BFL, the following Mathematical expression satisfies: BFL < D1, an effective diameter of the first lens may be larger than the effective diameters of the remaining lenses, and an effective diameter of the fourth lens may be smaller than the effective diameter of the first lens.

Inventors

  • KIM, JINYOUNG
  • Lee, Changhyuck
  • JUNG, Yukyeong

Assignees

  • LG INNOTEK CO. LTD
  • Hyundai Mobis Co., Ltd.

Dates

Publication Date
20260506
Application Date
20240628

Claims (15)

  1. An optical system comprising: first to fifth lenses aligned along an optical axis from an object toward a sensing unit; and an optical filter spaced apart from the sensing unit and disposed between the third lens and the fourth lens, wherein the first to fifth lenses include aspherical lenses and spherical lenses having a number of lenses greater than a number of aspherical lenses, wherein an optical axis distance from the optical filter to a surface of the sensing unit is D1, wherein an optical axis distance from a sensor-side surface of the fifth lens closest to the sensing unit to the surface of the sensing unit is BFL, wherein the following Mathematical expression satisfies: BFL < D 1 , wherein an effective diameter of the first lens is greater than effective diameters of the remaining lenses, and wherein the effective diameter of the fourth lens is smaller than the effective diameter of the first lens.
  2. The receiving optical system of claim 1, comprising: an aperture stop disposed on an object-side periphery of the optical filter, wherein an optical axis distance from the aperture stop to the surface of the sensing unit is SD, and wherein the following Mathematical expression satisfies: 1 < SD / D 1 < 1.2 .
  3. The receiving optical system of claim 1, wherein an optical axis distance from an object-side surface of the first lens to the optical filter is D2, and wherein the Mathematical expression satisfies: 0.5 < D 1 / D 2 < 1.5 .
  4. The receiving optical system of any one of claims 1 to 3, wherein the fourth lens and the fourth lens are spherical lenses, wherein the second lens is an aspherical lens, and wherein the fifth lens is an aspherical lens.
  5. The receiving optical system of claim 4, wherein the first lens is a spherical lens, wherein the effective diameter of the fourth lens is larger than the effective diameter of the first lens, and wherein the effective diameter is an average of the effective diameters of an object-side surface and a sensor-side surface of each lens.
  6. The receiving optical system of any one of claims 1 to 3, wherein a center thickness of the fifth lens is CT5, wherein an optical axis distance from a center of an object-side surface of the first lens to the surface of the sensing unit is TTL, and wherein the following Mathematical expression satisfies: CT 5 < TTL / 3 < D 1 .
  7. The receiving optical system of any one of claims 1 to 3, wherein the optical filter is a bandpass filter that passes light in the range of 890 nm to 960 nm, and wherein a center distance between the third lens and the fourth lens is the largest of center distances between the first lens to the fifth lens.
  8. The optical system of any one of claims 1 to 3, wherein the first lens includes a convex object-side surface and a concave sensor-side surface on the optical axis, and wherein an effective diameter of an object-side surface of the first lens is the largest among effective diameters of lens surfaces from the first lens to the fifth lens.
  9. The optical system of any one of claims 1 to 3, wherein the third lens has a biconvex shape on the optical axis, wherein the fourth lens has a meniscus shape convex toward the object, and wherein the fifth lens has a convex object-side surface and a concave sensor-side surface on the optical axis.
  10. The optical system of any one of claims 1 to 3, wherein the first lens has negative refractive power, wherein the fifth lens has positive refractive power, wherein the third and fourth lenses have positive refractive power.
  11. The receiving optical system of any one of claims 1 to 3, wherein Half of a diagonal length of the sensing unit is ImgH, wherein the optical axis distance from the optical filter to the surface of the sensing unit is D1, wherein the following Mathematical expression satisfies: ImgH < BFL < D1.
  12. The receiving optical system of claim 11, wherein an optical axis distance from a surface of the first lens to the surface of the sensing unit is TTL, wherein the following Mathematical expression satisfies: 20 mm < TTL < 60 mm, and wherein the first to fifth lenses are made of glass.
  13. A LIDAR device comprising: a transmitting optical system having a light source and first to fourth lenses aligned with a first optical axis from an object toward the light source; and a receiving optical system having a sensing unit and fifth to ninth lenses aligned along a second optical axis from an object side toward the sensing unit, wherein the fifth to ninth lenses include spherical lenses and aspherical lenses, wherein a number of spherical lenses is greater than a number of aspherical lenses in the receiving optical system, wherein the receiving optical system includes an optical filter disposed between the spherical lenses, wherein the transmitting optical system includes spherical lenses and aspherical lenses, wherein a number of aspherical lenses is smaller than a number of spherical lenses in the transmitting optical system, wherein the transmitting optical system includes an aperture stop and a diffuser disposed closer to the object side than the first lens, wherein a light emitting area of the light source is different from a light receiving area of the sensing unit, and wherein the first to fourth lenses and the fifth to ninth lenses are made of glass.
  14. The LIDAR device of claim 13, wherein the first lens of the transmitting optical system has a meniscus shape convex toward the object side and has positive power, and wherein the third lens has positive power.
  15. The LIDAR device of claim 14, wherein the fourth lens has a meniscus shape convex toward the object side and has negative power, and wherein an effective diameter of the third lens is larger than an effective diameter of the fourth lens.

Description

[Technical Field] An embodiment of the invention relates relates to an optical system and a sensor system having the same. An embodiment of the invention relates to an optical system for LIDAR (Light detection and ranging) and a device having the same. An embodiment of the invention relates to a mobile device having a transmitting optical system and system for LIDAR. An embodiment of the invention relates to a mobile device having a receiving optical system and system for LIDAR. [Background Art] ADAS (Advanced driving assistance system) is an advanced driver assistance system that assists the driver in driving, and is composed of sensing the situation ahead, judging the situation based on the sensed results, and controlling the vehicle's behavior based on the situation judgment. For example, the ADAS sensor device detects the vehicle ahead and recognizes the lane. Afterwards, when the target lane, target speed, and target ahead are determined, the vehicle's ESC (Electrical stability control), EMS (Engine management system), and MDPS (Motor driven power steering) are controlled. Representative examples of ADAS include automatic parking systems, low-speed city driving assistance systems, and blind spot warning systems. Recently, as interest in autonomous vehicles has increased, demand for LIDAR (Light detection and ranging) sensors, which are its core components, is increasing. Currently, LIDAR is only used for high-spec, expensive vehicles, but it is expected to be applied to general vehicles as well due to reduced manufacturing costs. Ultra-small and ultra-light LIDAR technology may be used not only as a sensor for unmanned mobile devices, but also in satellites and aerospace for observing the Earth's topography and environment, unmanned vehicles, transporters, cranes, and robots used in factories and shipyards, and is expected to emerge as a complex or cooperative operation between mobile devices through an integrated approach in the land, aviation, and marine industries, and as a result, it is urgent to develop an optical system for ultra-small and ultra-light LIDAR to implement ultra-small and ultra-light LIDAR. [Disclosure] [Technical Problem] An embodiment provides an optical system with improved optical characteristics and a sensor system having the same. An embodiment provides a wide-angle optical system and a sensor system having the same. An embodiment provides a wide-angle receiving optical system and a sensor system having the same. An embodiment provides a transmitting and receiving optical system, sensor system, and LIDAR device with improved heat compensation characteristics. [Technical Solution] A transmitting optical system according to an embodiment of the invention comprises first to fifth lenses aligned along an optical axis from an object toward a sensing unit; and an optical filter spaced apart from the sensing unit and disposed between the third lens and the fourth lens, wherein the first to fifth lenses include aspherical lenses and spherical lenses having a number of lenses greater than a number of the aspherical lenses, an optical axis distance from the optical filter to a surface of the sensing unit is D1, an optical axis distance from a sensor-side surface of the fifth lens closest to the sensing unit to the surface of the sensing unit is BFL, the following mathematical expression satisfies: BFL < D1, an effective diameter of the first lens may be larger than effective diameters of the remaining lenses, and the effective diameter of the fourth lens may be smaller than the effective diameter of the first lens. The receiving optical system includes an aperture stop disposed around an object-side periphery of the optical filter, and an optical axis distance from the aperture stop to the surface of the sensing unit is SD, and the mathematical expression satisfies: 1 < SD/D1 < 1.2. The optical axis distance from the object-side surface of the first lens to the optical filter is D2, and may satisfy the mathematical expression: 0.5 < D1/D2 < 1.5. The fourth lens and the fourth lens may be spherical lenses, the second lens may be an aspherical lens, and the fifth lens may be an aspherical lens. The first lens may be a spherical lens, the effective diameter of the fourth lens may be larger than the effective diameter of the first lens, and the effective diameter may be an average of the effective diameters of the object-side surface and the sensor-side surface of each lens. A center thickness of the fifth lens may be CT5, and the optical axis distance from the center of the object-side surface of the first lens to the surface of the sensing unit may be TTL, and may satisfy the mathematical expression: CT5 < TTL/3 < D1. In the receiving optical system, the optical filter is a bandpass filter that passes light in the range of 890 nm to 960 nm, and a center distance between the third lens and the fourth lens may be the largest among the center distances between the first lens to the fifth len