| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a spectroscope to be used in a vacuum ultraviolet ray range. <P>SOLUTION: In the spectroscope including a slit 40, a first achromatic lens 20, a grism 10, a second achromatic lens 30 and a detector 50, the first achromatic lens 20, the grism 10 and the second achromatic lens 30 are selected and formed by LiF, MgF2. The first achromatic lens 20 includes a first refractive lens 21 and a first diffractive lens 22 including a plurality of binary type diffractive lattices. The second achromatic lens 30 includes a second refractive lens 32 and a second diffractive lens 32 including a plurality of binary type diffractive lattices. The grism 10 is installed in between the first achromatic lens 20 and the second achromatic lens 30 and includes a prism 11 and diffractive lattices 12 having a plurality of binary type diffractive lattices. A mean square deviation value for the surface roughness of the binary type diffractive lattices of the first diffractive lens 22, the binary type diffractive lattices of the second diffractive lens 32 and the binary type diffractive lattices of the diffractive lattices of the grism 10 are 5 nm or less. <P>COPYRIGHT: (C)2012,JPO&INPIT |
