| 摘要 |
An optical system 400 includes two tilted elements 402, 404, such as prisms, each having two surfaces for which the sign of the slopes of at least three of the four surfaces that an incident beam eg 428 encounters are the same. When inserted into the path of the incident beam the system produces an output beam eg 438 having no angular deviation and little or no lateral deviation from the incident beam path. The two elements may be held by spacers (722,724, figure 7) or a planar support (418, figure 8) or may be joined together (figure 13). The figure 13 embodiment produces lateral beam deviation and beam concentration. |
