| 摘要 |
<p>PURPOSE: To facilitate manufacture and to turn a device to inexpensive constitution by making beams be provided with a narrowest contraction part on the exit surface of an illuminator by a condensing lens and a reflector. CONSTITUTION: The two condensing lenses 2 and 3 are arranged on the front side of a radiation source 1 and received radiation is bound to two sub-beams b. and b. by the lenses 2 and 3 and reflected in the direction of a main axis by first reflectors 4 and 5. Also, second reflectors 6 and 7 for constituting a roof mirror are arranged on both sides of the main axis OO' at a position where the beams are crossed with each other and a beam cross section is already small and the beams are deflected in the direction of the main axis by the reflectors. In this case, the beams are provided with the narrowest contraction part on the exit surface 10 of this illuminator. Thus, in the device for which it is required to use the illuminator, the need of using an expensive optical element provide with a large opening number or a large cross section for instance is eliminated.</p> |
