JP2017219345A - Apparatus for measuring vehicle headlight - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem that light likely to be light distribution except light distribution on the basis of a vehicle headlight may enter on a light distribution screen in an apparatus for measuring a conventional vehicle headlight, and the cause is unknown.SOLUTION: An apparatus for measuring a vehicle headlight comprises: a fresnel lens 11 for condensing the headlight beam of a vehicles to be measured; a light distribution screen 8 for receiving light distribution converging from the fresnel lens 11; a camera 9 for detecting the received light distribution; and a display 5 for displaying the light distribution detected by the camera 9. A light distribution processing layer, such as a light diffusion layer, a light absorption layer, a light reflection layer or an internal reflection light suppression layer is formed on the non-lens surface 10b of the fresnel lens 11.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a vehicle headlight measuring apparatus.

  The vehicle headlight (headlight) needs to satisfy various conditions, for example, so as not to dazzle the oncoming vehicle. Therefore, it is necessary to measure the optical axis of the vehicle headlight, the cut-off line of the light distribution, the elbow point, the balance point of the light intensity, etc. at the time of vehicle inspection, and inspect whether the measured value is within the allowable range. .

  As such a measuring device, for example, there is a measuring device for a vehicle headlight described in Patent Document 1.

  3 and 4 show the conventional vehicle headlight measuring device 1 as shown in FIG. 3. The measuring device 1 is a carriage 2 that moves in the left-right direction on a rail laid on the floor as shown in FIG. A column 3 erected on the carriage 2, a rectangular parallelepiped housing 4 provided on the column 3 so as to be movable up and down, a display device 5 such as a liquid crystal monitor provided on the housing 4, and an arithmetic storage processor 6. It consists of and.

  In addition, as shown in FIG. 4, the housing 4 has a Fresnel lens 7 fixed to the front surface of the housing 4 for receiving the headlight light of the vehicle under measurement. A light distribution screen 8 for receiving the light distribution converged from the Fresnel lens 7 is fixed to the rear, and the light distribution received by the light distribution screen 8 is detected in the middle upper part of the housing 4. An imaging camera 9 such as a CCD camera is fixed.

  In the conventional vehicle headlight measuring device, the light distribution of the headlight received on the light distribution screen 8 is imaged by the imaging camera 9, and the light distribution detected by the camera 9 is displayed on the display device. The measured position such as the optical axis, cut-off line, elbow point, and luminous intensity balance point was inspected from the displayed image.

JP 2008-39729 A

  However, in some cases, the light distribution image of the vehicle headlight received on the light distribution screen sometimes has a light distribution other than the light distribution based on the vehicle headlight. It is unclear whether it is based on a vehicle headlight or other, and in particular, no investigation of the cause has been made.

  The present inventor notices that the unknown light distribution enters the light distribution image on the light distribution screen when the vehicle headlight is a headlight having a strong light source such as a projector lamp, and a strong light source. If it occurs in the case of a headlight having a light source, it has been found that the cause lies in the Fresnel lens, and the present invention has been achieved.

  In order to achieve the above object, the present invention provides a headlight measuring device comprising: a Fresnel lens for condensing headlight light of a vehicle to be measured; and a light distribution screen for receiving a light distribution converged from the Fresnel lens. And a camera for detecting the received light distribution and a display device for displaying the light distribution detected by the camera, wherein a light distribution processing layer is formed on a non-lens surface of the Fresnel lens, To do.

  Further, the light distribution processing layer is a light diffusion layer, a light absorption layer, a light reflection layer, or an internal reflection light suppression layer.

  According to the vehicle headlight measuring device of the present invention, even if a strong light source headlight such as a projector lamp is used, the light from the non-lens surface subjected to the light distribution process is dispersed and the like on the light distribution screen. Light distribution other than the light distribution based on the vehicle headlight is less likely to occur.

It is a top view of the Fresnel lens of the measuring device of the headlight for vehicles of the present invention. It is an enlarged vertical side view of a part of the Fresnel lens. It is a front view of the conventional measuring device of the headlight for vehicles. It is a vertical side view of the housing | casing of this measuring apparatus.

  Embodiments of the present invention will be described below with reference to the drawings.

  In the present invention, in a Fresnel lens of a conventional vehicle headlight measurement device, a light distribution layer such as a light diffusion layer, a light absorption layer, a light reflection layer, or an internal reflection light suppression layer is provided on the non-lens surface. The formed Fresnel lens is used.

  That is, as shown in FIGS. 1 and 2, in the Fresnel lens 11 in which a ring-shaped lens portion 10 having a mountain-shaped cross section composed of a lens surface 10a and a rising surface (non-lens surface 10b) is continuously formed, A light distribution processing layer such as a light diffusion layer, a light absorption layer, a light reflection layer, or an internal reflection light suppression layer is formed on the entire surface of the surface 10b.

  As shown in FIG. 1, the lens surface 10a is a convex surface or concave surface that performs a lens action, and the non-lens surface 10b has a lens action formed in a substantially vertical direction. It's not a side.

  2 indicates the direction in which the headlight of the vehicle under test comes, and the Fresnel lens 11 has a surface from which the lens surface 10a and the non-lens surface 10b of the Fresnel lens 11 are continuous. It is installed in the housing of the measuring device so that headlight light is incident. However, the Fresnel lens 11 is installed in the housing of the measuring apparatus so that headlight light enters from the opposite side of the surface where the lens surface 10a and the non-lens surface 10b of the Fresnel lens 11 are continuous. May be.

  The light diffusion layer is applied to the non-lens surface, for example, fine irregularities (fine projections) having a surface roughness of 1 μm Rt or more, such as a satin (snaji) formed on the non-lens surface, for example. It consists of a light diffusing paint. The surface roughness is not limited to the above range.

  The light absorption layer is made of a light absorber such as black ink applied to the non-lens surface, for example.

  The light reflecting layer is made of, for example, a metal film that reflects light and is deposited on the non-lens surface.

  In addition, the internal reflection light suppression layer is formed of, for example, irregularities that are formed on the non-lens surface and suppress reflection light inside the Fresnel lens from being emitted from the non-lens surface.

  In a general Fresnel lens, both the lens surface and the non-lens surface are mirror-finished, and when a headlight lamp having a strong light source is measured using a headlight measuring device using such a Fresnel lens, the non-lens surface In some cases, the light distribution from the non-lens surface may be reflected on the light distribution screen. However, in the present invention, the light diffusion layer or the light absorption may be reflected. Even if a headlight having a strong light source is used by using a Fresnel lens having a non-lens surface on which a light distribution processing layer such as a layer, a light reflection layer, or an internal reflection light suppression layer is formed (applied), The light distribution on the lens surface is dispersed by the light diffusion layer, the light is absorbed by the light absorption layer, the light is reflected by the light reflection layer, or the light is internally reflected. Since the suppression layer does not emit the lens interior light, the unknown light distribution is not generated on the light distribution screen.

  The headlight measuring device of the present invention is useful in a vehicle maintenance factory or the like that performs a manufacturing process or vehicle inspection and maintenance of passenger cars and other automobiles.

DESCRIPTION OF SYMBOLS 1 Measuring apparatus 2 Carriage 3 Support | pillar 4 Case 5 Display apparatus 6 Arithmetic storage processing apparatus 7 Fresnel lens 8 Light distribution screen 9 Imaging camera 10 Lens part 10a Lens surface 10b Non-lens surface 11 Fresnel lens

Claims (2)

A Fresnel lens that condenses the headlight light of the vehicle under measurement;
A light distribution screen for receiving the light distribution converged from the Fresnel lens;
A camera for detecting the received light distribution;
A display device that displays the light distribution detected by the camera;
A vehicle headlight measuring device, wherein a light distribution processing layer is formed on a non-lens surface of the Fresnel lens.   The vehicle light distribution measuring device according to claim 1, wherein the light distribution processing layer is a light diffusion layer, a light absorption layer, a light reflection layer, or an internal reflection light suppression layer.

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