JP2009265068A - Light source apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To overcome the problem that a collective lens necessarily becomes long, needs to be used in a tandem manner and easily makes a shadow at a joint if a long object is inspected, an accurate inspection apparatus can not be obtained because the shadow is determined as a defect in the object, and the long collective lens is very expensive although it can be manufactured as a customized collective lens. <P>SOLUTION: A plurality of chip LEDs are disposed at a regular interval. A plurality of the collective lenses are jointed, and disposed on a plurality of the LEDs. A diffusion film is arranged on them at a distance of ≥10 mm. As a result, nonuniformity of the light quantity is overcome, and the inexpensive commercial collective lens can be used. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a high-intensity light source device that inspects a defect of a long inspection object by combining a chip-shaped LED, a condenser lens, and a diffusion film.

  Conventionally, fluorescent lamps have been the mainstream as light sources for defect inspection devices, but in recent years, high-brightness LEDs have been developed, and multiple LEDs arranged in place of fluorescent lamps are used as the light source because of advantages such as long life and power saving. It has come to be.

  This LED was initially used as a bullet-type with a lens and LED integrated. However, when finding defects such as scratches on the inspection object, the light source brightness was not sufficient, and a small defect was detected on the inspection object. It was difficult to do. Therefore, a high-intensity light source device combining a chip-shaped LED, a condenser lens, and a diffusion film is provided.

  However, in order to inspect a long object with such an apparatus, the length of the condensing lens becomes inevitably long, and the condensing lens must be added and used. For this reason, it becomes easy to make a shadow at the joint of the condensing lens, and this shadow is judged to be a defect of the inspection object, and an accurate inspection device cannot be provided.

  In order to eliminate this shadow, it is possible to manufacture a long condensing lens by custom order, but there is a disadvantage that it is very expensive. Moreover, a rod lens, a cylindrical lens, etc. are used for the condensing lens, and the diffusion film is attached on this.

In order to solve the above-mentioned problem, the present invention arranges a plurality of chip-shaped LEDs at equal intervals, arranges a condensing lens added on the plurality of LEDs, and disperses a diffusion film by separating them by 10 mm or more. installed.

  According to the present invention, a condensing lens such as a rod lens or a cylindrical lens that is connected to the upper part of a plurality of chip-like LEDs arranged in a long straight line is provided, and is diffused at least 10 mm away from the condensing lens. By installing the film, there is no shadow on the joint of the condenser lens, and a uniform amount of light can be obtained. Further, since a special long condensing lens is not used, the cost is very low.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is an explanatory view of a light source device showing an embodiment of the present invention.

In this light source device, rod lenses 7 and 8 are mounted on chip-shaped LEDs 1, 2, 3, 4, 5 and 6 mounted on a printed circuit board 11 on a heat radiating fin 10. Naturally, if the length of the light source device is increased, the number of chip-shaped LEDs and the number of rod lenses increase.
A diffusion film 9 is attached to the upper part of the rod lenses 7 and 8.

Chip-shaped LEDs 1, 2, 3, 4, 5, 6 are mounted in a line at equal intervals. Further, the rod lenses 7 and 8 are inexpensive and have a short length sold on the market. Table 1 shows the amount of unevenness of light quantity through the diffusion film when the distance L between the rod lenses 7 and 8 and the diffusion lens 9 is changed.

  With the configuration as described above, in this embodiment, before the light flux from the LED spreads, it is collected in the rod lenses 7 and 8 without leakage, and the light flux emitted from the rod lenses 7 and 8 is converted into linear parallel rays by the diffusion film 9. And irradiated outside. The luminous flux from the LED is efficiently amplified by the rod lenses 7 and 8, so that sufficient luminance is obtained. However, from the experimental results in Table 1, the distance between the rod lenses 7 and 8 and the diffusion film 9 is 10 mm or more, and the amount of light is uneven. It will be resolved.

Explanatory drawing of the light source device which shows the Example of this invention.

Explanation of symbols

1,2,3,4,5 ... Chip LED
7, 8 ... Rod lens 9 ... Diffusion film 10 ... Radiation fin 11 ... Printed circuit board

Claims (1)

  A light source device in which a plurality of chip-shaped LEDs are arranged at equal intervals, a condensing lens added on the plurality of LEDs is arranged, and a diffusion film is installed on the LED by a distance of 10 mm or more.

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