JP2011238577A - Light source device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light source device which inspects a fault of an inspection object using an LED, and in which halation by reflection from the inspection object is prevented.SOLUTION: Chip-shape LEDs 1, 2 are installed on hypotenuses of saw shape with an angle of about 90° and a ball lens 3 of a size that can contact the surface of nearly two pieces of LEDs is fixed between the two pieces of LEDs installed on the hypotenuses. A light shielding plate with a hole is arranged so that the luminous flux from the chip-shape LEDs may be irradiated through the ball lens at an angle of about 45°.

Description

  The present invention relates to a light source device that effectively inspects defects of an inspection object by combining a chip-like LED and a ball lens.

  Conventionally, fluorescent lamps have been mainly used as light sources for defect inspection devices, but in recent years, LEDs with high illuminance have been developed, and multiple LEDs arranged in place of fluorescent lamps have been adopted as light sources 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 an integrated lens and LED. However, when finding defects such as scratches on the inspection object, the light source is usually placed perpendicular to the inspection object. Yes. The light emitted from the bullet-type LED has a narrow radiation angle, and most of the light is emitted only from directly above the LED, and the reflected light from the inspection object is reflected directly below, causing halation. If the defect of the inspection object is large, it can be found, but if it is a small defect, it is likely to be missed. Therefore, as shown in FIG. 2, bullet-type LEDs 8 tilted at approximately 45 degrees are arranged on the printed circuit board 9 in two opposite directions in the left and right directions so as not to cause halation by the reflected light from the inspection object.

  Further, FIG. 3 shows that chip-shaped LEDs 10 and 11 are used and a plurality of LEDs are arranged at equal intervals with a pitch P, and a ball lens 13 having a diameter of approximately P is fixed between the chip-shaped LEDs 10 and 11. In this method, the luminous flux from the chip-like LED is irradiated through the ball lens 13 at an angle of approximately 45 degrees so that the reflected light from the inspection object does not cause halation.

  FIG. 2 shows an embodiment of a light source device in which a plurality of bullet-type LEDs that are generally used in the past are arranged in two opposite directions in the left and right directions and are inclined at approximately 45 degrees. In this device, it is necessary to tilt the bullet-type LED to approximately 45 degrees and attach it to a printed circuit board or the like. Therefore, processing such as matching the tilt is difficult, and the mounted state is highly variable, and the light uniformity is poor. Since they are arranged in a row, there is a disadvantage that the number of bullet-type LEDs increases and becomes expensive.

  Further, FIG. 3 using a chip-like LED has a defect that sufficient illuminance cannot be obtained because only a part of the light flux emitted from the LED is irradiated through the ball lens.

  In order to solve the above-mentioned problems, the present invention has a chip-like LED installed on a saw-like hypotenuse having an angle of approximately 90 °, and approximately two LED surfaces between the two LEDs attached to the hypotenuse. A ball lens having a size in contact with the lens was fixed, and a light-shielding plate with a hole was arranged so that the light flux from the chip-shaped LED was irradiated through the ball lens at an angle of approximately 45 degrees.

  As described above, according to the present invention, a chip-like LED is installed on a saw-like oblique side having an angle of approximately 90 °, and approximately two LED surfaces are disposed between two LEDs attached to the oblique side. By fixing the ball lens of the size in contact with it, the light flux from the chip-shaped LED is irradiated through the ball lens at an angle of approximately 45 degrees, so that not only the light flux of approximately 45 degrees can be emitted uniformly, but also the LED Sufficient illuminance can be obtained by using the luminous flux emitted from the center.

  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.

  This light source device includes printed circuit boards 4 and 5 installed on a saw-shaped heat radiation metal plate 6 having an angle of 90 °, chip-shaped LEDs 1 and 2, ball lens 3 and LED 1 mounted on the printed circuit board. , 2 light shielding portion 7a and light emitting hole 7b. Naturally, as the length of the light source device increases, the number of chip-shaped LEDs and ball lenses increases.

  The chip-shaped LEDs 1 and 2 are attached to printed circuit boards 4 and 5 installed on a saw-like heat-dissipating metal plate 6, and the ball lens 3 is placed on the upper portions of the LEDs 1 and 2 so as to be substantially in contact with the central portion of the LEDs 1 and 2. Is fixed. The light shielding plate 7 has a light emission hole 7b so that the light flux from the chip-like LED can be irradiated at approximately 45 degrees through the ball lens, and is attached to the upper end of the ball lens so that only the light flux through the ball lens is emitted. Yes.

  With the configuration as described above, uniform irradiation light of approximately 45 degrees in which no halation occurs is obtained in the present embodiment, and sufficient luminous intensity is obtained because the light beam emitted from the central portion of the LED is irradiated through the ball lens.

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

1,2 ... Chip LED
3... Ball lens 4, 5... Printed circuit board 6... Saw-like heat sink 7. Light emission hole 8 of the light shielding plate 7 ... bullet-type LED
9 ... Printed circuit board 10, 11 ... Chip LED
12 ... Printed circuit board 13 ... Ball lens 14 ... Shading plate

Claims (1)

    A chip-shaped LED is installed on a saw-shaped hypotenuse having an angle of approximately 90 °, and a ball lens having a size in contact with the surface of two LEDs is fixed between the two LEDs mounted on the hypotenuse. A light source device in which a light shielding plate having a hole is arranged so that a light beam from a chip-like LED is irradiated through a ball lens at an angle of approximately 45 degrees.

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