| 摘要 |
PURPOSE:To make it possible to perform highly accurate measurement of light, by enclosing a condenser lens in a lens holder having an eccentric outer diameter, and providing an fixing metal, which makes it possible to rotate said holder, on the base of a spectroscope. CONSTITUTION:Light from a lamp 1 is diffracted by a concave diffraction grating 5 through a condenser lens 2, a measuring cell 3, and an incident slit 4. At this time, the outer diameter of a lens holder 8, wherein the lens 2 is enclosed, is eccentrically moved by (e). The holder 8 is rotatably coupled into an attaching metal 10. The holder 8, the lamp 1, and the like are all provided on one straight line on a base 7. The distance between the lens 2 and the slit 4 is made to be, e.g., three times the distance between the lens 2 and the lamp 1. Then, the metal 10 is rotated by 180 degrees and moved by 2e. An image is formed at the position where movement of 6e is performed. The image can be made to agree with the slit 4. |
