Lightweight optical system suitable for handheld laser range finder

Abstract

The utility model relates to a lightweight optical system suitable for a hand-held laser range finder, the optical system comprises a transmitting antenna and a receiving antenna, the transmitting antenna comprises a first plano-convex lens, a laser beam emitted by a laser diode passes through the first plano-convex lens to form a collimated beam, and the shaped laser beam is incident to the surface of a ranging target; the receiving antenna comprises a second plano-convex lens and a right-angle reflecting prism, laser beams reflected by the surface of a ranging target are shaped and converged through the second plano-convex lens, a receiving light path is reflected to the photosensitive surface of the detector through the right-angle reflecting prism, and the first plano-convex lens and the second plano-convex lens are both made of black PMMA materials. And the receiving light path shortens the light path structure through the reflecting mirror, so that the light weight of the optical system is realized.

Description

Technical Field

[0001] The utility model relates to the technical field of laser and optoelectronics, and in particular to a lightweight optical system suitable for a handheld laser rangefinder. Background Art

[0002] The laser rangefinder consists of three parts: the laser transmitting component, the laser receiving component and the circuit component. The structure of the rangefinder is mainly composed of the optical system structure, and other components are supplementary. The optical system not only affects the ranging performance, but also greatly affects the overall structural design. The simplification of the optical system structure is conducive to the overall structure to achieve lightweight and reduce material costs. Handheld laser rangefinders have high requirements for lightweight and miniaturization because they are handheld.

[0003] Optical glass has the advantages of low cost, high light transmittance and high temperature resistance. Optical components in optical systems are generally made of glass, but glass has the disadvantages of being large, heavy and fragile. In order to pursue optical system performance and lightweight structure, the optical system structure, optical component material selection and processing technology have become the main optimization directions of the optical system. Utility Model Content

[0004] In view of the defects of the prior art, the utility model designs a lightweight optical system suitable for a handheld laser rangefinder.

[0005] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0006] A lightweight optical system suitable for a handheld laser rangefinder comprises a transmitting antenna and a receiving antenna, wherein the transmitting antenna comprises a first plano-convex lens, wherein the incident surface of the first plano-convex lens is a plane, and the exit surface is a spherical surface, and the receiving antenna comprises a second plano-convex lens and a right-angle reflecting prism, which are sequentially arranged along the propagation direction of a light beam, wherein the incident surface of the second plano-convex lens is a spherical surface, and the exit surface is a plane, and the right-angle reflecting prism folds the light beam emitted by the second plano-convex lens by 90 degrees and then reflects it to a photosensitive surface of a detector, and the first plano-convex lens and the second plano-convex lens are both made of black PMMA material.

[0007] Furthermore, the inclined surface of the right-angle reflecting prism is coated with an aluminum reflecting film.

[0008] Furthermore, the material of the right-angle reflection prism is H-K9L.

[0009] Furthermore, the first plano-convex lens and the second plano-convex lens are both manufactured by a molding process.

[0010] Beneficial effects: The optical system structure of the present utility model is used in a handheld laser rangefinder. It has a simple structure and few optical elements. The first plano-convex lens and the second plano-convex lens are made of black PMMA material. Compared with optical glass, it can greatly reduce the weight of the optical system. The right-angle reflecting prism deflects the light, reducing the system length. The entire optical system is characterized by light weight and small size, and can well meet the usage requirements of the handheld laser rangefinder. Description of the Drawings

[0011] Figure 1 The transmitting antenna configuration of the present utility model;

[0012] Figure 2 The receiving antenna configuration of the present utility model;

[0013] Reference numerals: 1, the first plano-convex lens; 2, the second plano-convex lens; 3, the right-angle reflecting prism. Detailed Embodiment

[0014] The following further describes the present utility model in detail with reference to the drawings and specific embodiments.

[0015] As Figure 1-2 shown, a lightweight optical system applicable to a handheld laser rangefinder of the present utility model includes a transmitting antenna and a receiving antenna. The transmitting antenna and the receiving antenna are respectively arranged in the transmitting antenna housing and the receiving antenna housing of the laser rangefinder. The transmitting antenna includes a first plano-convex lens 1, whose incident surface is a plane and the exit surface is a spherical surface. The first plano-convex lens 1 collimates the laser beam emitted by the laser diode and compresses the divergence angle. The collimated laser beam irradiates the surface of the ranging target. The receiving antenna includes a second spherical lens 2 and a right-angle reflecting prism 3, which are arranged in sequence along the propagation direction of the light beam, and are used to converge and condense the laser reflected by the measured target and deflect the optical path. Among them, the incident surface of the second plano-convex lens 2 is a spherical surface and the exit surface is a plane. The second plano-convex lens 2 converges and condenses the laser reflected from the surface of the measured target, and the right-angle reflecting prism 3 deflects the converged light beam by 90° and then reflects it to the photosensitive surface of the receiving detector.

[0016] The specific parameters of the optical system structure in the present utility model are as follows:

[0017] The outer diameter of the first plano-convex lens 1 is D = 7.2 mm, the radius of curvature R1 = ∞, the radius of curvature R2 = -14.55 mm ± 0.5 mm, the central thickness d = 3 mm ± 0.1 mm, and the material is black PMMA.

[0018] The outer diameter of the second plano-convex lens 2 is D = 19 mm, the radius of curvature R1 = 13.243 mm ± 0.5 mm, the radius of curvature R2 = ∞, the central thickness d = 5.2 mm ± 0.1 mm, and the material is black PMMA.

[0019] The external dimensions of the right-angle prism 3 are 5mm * 5mm * 5mm, the size of the reflecting surface is 7.07mm * 7.07mm, and the material is H-K9L.

[0020] The optical antenna only includes a first plano-convex lens, a second plano-convex lens and a right-angle reflecting prism, which can reduce the number of optical elements without affecting the performance of the optical system.

[0021] The transmitting antenna includes a first plano-convex lens. After being shaped by the transmitting antenna, the divergence angle of the laser emitted by the laser diode is 6mrad.

[0022] The first plano-convex lens 1 and the second plano-convex lens 2 selected in the present utility model are both made of PMMA material, and the weight is one-half of that of ordinary glass. The total weight of the optical system is < 2g, which has the advantages of light weight and small volume, and is beneficial to realizing the lightweight of the structure.

[0023] The PMMA material used for the second plano-convex lens 2 can inhibit the passage of the 250 - 700nm band, has a high transmittance at the central wavelength of 905nm, can filter stray light, and inhibits the optical noise of the receiving component.

[0024] Both the first plano-convex lens 1 and the second plano-convex lens 2 are processed by the molding process, with low price cost and high production efficiency.

[0025] The inclined surface of the right-angle reflecting prism 3 is coated with an aluminum reflecting film, which uses the principle of total reflection to deflect light, and can shorten the length of the optical antenna and the overall structure length.

[0026] The above is only the preferred embodiment of the present utility model, and does not impose any form of limitation on the present utility model. Although the present utility model has been disclosed above with the preferred embodiment, it is not intended to limit the present utility model. Any person skilled in the art can make some changes or modifications to the above-disclosed technical content to be equivalent embodiments within the scope of the technical solution of the present utility model. However, as long as it does not depart from the content of the technical solution of the present utility model, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present utility model still fall within the scope of the technical solution of the present utility model.

Claims

1. A lightweight optical system applicable to a handheld laser rangefinder, comprising a transmitting antenna and a receiving antenna, characterized in that, The transmitting antenna includes a first plano-convex lens, the incident surface of the first plano-convex lens is a plane, and the exit surface is a spherical surface. The receiving antenna includes a second plano-convex lens and a right-angle reflecting prism, which are arranged in sequence along the propagation direction of the light beam. Among them, the incident surface of the second plano-convex lens is a spherical surface, and the exit surface is a plane. The right-angle reflecting prism deflects the light beam emitted by the second plano-convex lens by 90° and then reflects it to the photosensitive surface of the detector. Both the first plano-convex lens and the second plano-convex lens are made of black PMMA material.

2. The lightweight optical system applicable to a handheld laser rangefinder according to claim 1, wherein The inclined surface of the right-angle reflecting prism is coated with an aluminum reflecting film.

3. The lightweight optical system applicable to a handheld laser rangefinder according to claim 1, characterized in that, The material of the right-angle reflecting prism is H-K9L.

4. A lightweight optical system applicable to a handheld laser rangefinder according to claim 1, characterized in that, Both the first plano-convex lens and the second plano-convex lens are processed by a molding process.

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