| 摘要 |
PURPOSE:To obtain a miniature and simple optics head with low cost by using a focusing rod lens of a large caliber which turns the beams given from a light source into parallel ones to form a collimator lens system. CONSTITUTION:For a collimator lens system, the beams radiated from a laser light source 201 are turned into parallel beams 206 through a focusing rod lens 203 of a large coliber which has a microfocus surface and a short focus with about 10mm. length. Therefore an optical path of about 10mm. suffices with the lens system. This can solve a problem where the size of an optical head is increased owing to the size of the collimator lens system. Furthermore both manufacturing processes, the material cost, etc. can be reduced since the production is not needed for plural microlenses. In addition, the lens 203 can be unified with the source 201 or a polarizing prism 207. This can omit additional parts such as a spacer, a lens holder, etc. As a result, the constitution of an optical head is simplified. |
