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KR-102962770-B1 - LENS SYSTEM FOR INFRARED RAYS

KR102962770B1KR 102962770 B1KR102962770 B1KR 102962770B1KR-102962770-B1

Abstract

The present invention is characterized by an infrared lens system comprising a lens having an aspherical first surface (S1) that primarily refracts light incident from an object and an aspherical convex second surface (S2) that secondarily refracts light passing through the first surface (S1), wherein the radius of curvature of the first surface and the second surface are -9.24858 mm and -3.014753 mm, respectively, the thickness of the lens is 2.750 mm, the refractive index of the lens is 2.61, and the Abbe number of the lens is 108.53, so as to be able to operate inside a vehicle even in extreme vehicle environments and recognize objects in blind spots.

Inventors

  • 유준혁
  • 김미선
  • 최현태
  • 이중관

Assignees

  • (주)에이지광학

Dates

Publication Date
20260512
Application Date
20231005
Priority Date
20221005

Claims (5)

  1. In an infrared lens system, A lens comprising an aspherical first surface (S1) that primarily refracts light incident from a subject, and an aspherical convex second surface (S2) that secondarily refracts light passing through the first surface (S1), The radii of curvature of the first surface and the second surface are -9.24858 mm and -3.014753 mm, respectively, and The thickness of the above lens is 2.750 mm, and The refractive index of the above lens is 2.61, and The Abbe number of the above lens is 108.53, and The first surface of the lens is concave, and the second surface of the lens is convex, and An infrared lens system in which each face is derived and specified by <Equation 1> . <Equation 1> [Table 1]
  2. In paragraph 1, The above-mentioned lens material is chalcogenide, an infrared lens system.
  3. In paragraph 1, An infrared lens system having a focal length of 2.2 mm.
  4. In paragraph 1, An infrared lens system having an angle of view of 80˚.
  5. delete

Description

Infrared Lens System The present invention relates to an infrared lens system, and more specifically, to an infrared lens system capable of ensuring high resolution inside a vehicle even in extreme field environments such as extreme cold and extreme heat. Recently, extreme weather events such as heatwaves, heavy snowfall, and cold waves have become more frequent, and vehicles are operating while directly exposed to these extreme environments. In particular, there was a recent incident where a child left in a daycare shuttle during a heatwave was found dead. Children cannot easily get out of a vehicle when left alone, and the temperature inside a vehicle parked under strong sunlight can rise to over 70 degrees Celsius during the hot summer. Such accidents can be prevented simply by adults looking around the interior of the vehicle. To this end, a device has been developed that installs a button at the rear of the vehicle, requiring the button to be pressed to turn off the engine and lock the doors. In other words, because the driver must go to the back of the vehicle to press this button after finishing a trip, it allows them to check if there are any children left behind, such as those who have fallen asleep or are playing hide-and-seek. As an alternative approach utilizing smartphone functions such as Near Field Communication (NFC), a device has been developed that sounds an alarm on the driver's mobile phone when the vehicle's engine is turned off and requires the smartphone to be tapped on NFC tags attached throughout the vehicle to stop it. Both of the above two methods are devices that help teachers or bus drivers check the interior of the vehicle, but since a person must physically move and visually check the interior of the vehicle, there was a problem in that a child inside the vehicle could not be recognized if visual identification was impossible. In addition, there are cases where video of the vehicle interior is checked using CCTVs inside the vehicle, but since existing CCTVs use visible light to capture images, there was a problem in that it was difficult to recognize the child in the video when the child was in a blind spot obscured by the seats inside the vehicle. FIG. 1 is a schematic diagram of an infrared lens system according to a first embodiment of the present invention, Figures 2 to 6 are graphs of the MTF curves of the infrared lens system of Figure 1. Before the explanation, in various embodiments, components having the same configuration will be described using the same reference numerals. Hereinafter, a lens system for image capture according to the first embodiment of the present invention will be described in detail with reference to the attached drawings. FIG. 1 is a schematic diagram of an infrared lens system according to a first embodiment of the present invention. Referring to FIG. 1, the infrared lens system according to a first embodiment of the present invention is configured to include an aperture (ST), a lens (10), an optical filter (20), and an image sensor (30) from a subject. The above aperture (ST) is a means for controlling the amount of light incident on the lens. In the description of the lens shape above, the meaning that one surface is convex means that the paraxial region of that surface is convex, and the meaning that one surface is concave means that the paraxial region of that surface is concave. Therefore, even if one surface of the lens is described as having a convex shape, the edge of the lens may be concave. Similarly, even if one surface of the lens is described as having a concave shape, the edge of the lens may be convex. The term "paraxial region" above refers to a very narrow area near the optical axis. The lens (10) has an aspherical first surface (S1) that primarily refracts light incident from a subject and an aspherical second surface (S2) that secondarily refracts light that has passed through the first surface (S1). Here, the first surface (S1) is formed concavely in the paraxial region, and the second surface (S2) is formed convexly in the paraxial region. At this time, the first surface (S1) and the second surface (S2) are formed as aspherical surfaces as described above, thereby minimizing the resolution variation by image area. Meanwhile, the first surface (S1) and the second surface (S2) are specified by the following formula 1, Table 1 and 2, and the infrared lens system according to the first embodiment of the present invention is characterized by having a field of view of 80˚. <Equation 1> Here, K represents the conic surface coefficient, A, B, C, and D represent the aspheric coefficients, Y represents the height of the ray incident on the lens, and c represents the lens curvature. noodleRadius of curvature (1/c)Lens thickness (d)Material InformationRefractive index (n)Abesu (v)S1-9.248582.7502.61108.53S2-3.014753 Meanwhile, the focal length of the lens of the present invention is characterized as being 2.20 mm, and the focal length