| 摘要 |
<p>PURPOSE:To improve functionality of a photographing device by providing an observation translucent window at the lower and also providing a light source and its reflection section and a light guide section for guiding a reflected light downward in an outer casing in which a TV camera is enclosed. CONSTITUTION:A translucent window 4 is provided at the lower end, the entire lower circumference is formed of a light guide section 5 consisting of transparent glass, and a watertight outer casing 1 whose upper end is made a reflection section 6 is provided. Then, a conical cylindrical shade hood 7 is provided in the casing 1 and plural light source lamps 3 are disposed around the hood. Then, a TV camera 2 is provided above the hood 7 to allow photographing the conditions of the borehole inside while the well borehole inside is illuminated by radiation beams from the light guide section 5. In addition, the camera 2 may be disposed in the lower section of the outer casing 1 with one lamp provided above the camera or the light guide section may be formed of a metal plated double cylindrical pipe or glass fiber bundles. This allows the device to be compact and vivid images to be photographed without halation.</p> |
