| 摘要 |
PURPOSE:To easily measure the thickness of an ink film, to improve the performance of a printer and to save the labor by measuring the spread of an image from data sent from a detector which photodetects the image formed with laser light, calculating the thickness of the ink film from the measured value. CONSTITUTION:This measuring instrument consists of a laser light emitting device 1, a converging lens 2, a camera 4, a frame memory 5, a data gathering computer 6, etc. Then the laser light is projected on an ink surface on the surface of a roller 3 and the spot image of the projection light formed on the ink surface is inputted to the camera 4 in a direction slanting by an angle phito the direction of the roller shaft. Its signal is supplied to a memory 5 and one image plane is decomposed into many picture elements, and their brightness values are classified by grades, and the results are calculated 6 to find the spread of the spot. At this time, the best value corresponding to the kind of ink is selected as the angle phi of the camera 4 and this spread is evaluated by providing a threshold value at a position of, for example, 10% brightness, thereby easily measuring the ink film thickness.
|
