Optical system for altering form of laser beam cross section - has follow-on lenses with offset axial angles and max. focus of 300 mm

摘要

The method for changing the beam cross section, especially from laser diodes which in different emission planes send out light at different angles. The features provide at least two cylindrical lenses whereby the cyinder axis of the two are inclined against each other, up to an angle of 20 degrees. The focal distances of the two lenses of which the first is widening the beam and the second is concentrating the beam, shall be no less than 1 mm and no more than 300 mm. In a cited example a focal distance of about 9 mm was used. The method, therefore, provides for relatively compact beam shape correction techniques. ADVANTAGE - Beam emissions from laser diodes can be inexpensively homogeonised to obtain any desired cross section e.g. cylindrical, elliptical.