公开(公告)号：GB697207A

公开(公告)日：1953-09-16

申请号：GB2861551

申请日：1951-12-06

Applicant: BECKMAN INSTRUMENTS INC

Inventor： MILLER WILLIAM CURTIS

IPC: G01J3/16

Abstract: 697,207. Spectroscopic apparatus. BECKMAN INSTRUMENTS, Inc. Dec. 6, 1951, No. 28615/51. Class 97 (i). A monochromator, or other spectroscopic apparatus comprises a Fery prism having a spherical front surface which is refractive and a spherical rear surface which is reflective, the centres of curvature of these surfaces being spaced apart along the circle diagram of the prism on which diagram is also an entrance slit located so that rays therefor are incident at substantially equal angles i on the front surface and are refracted thereby so as to be substantially normal to the rear surface whence they are reflected, refracted once again, and form a spectrum, the entrance slit being curved to a radius R equal to n 2 . f.cotan i/2(n 2-1 ), where f is the focal length of the prism and n its refractive index, whereby a substantially linear image of the entrance slit is produced. Fig. 1 shows a curved entrance slit 12 light from which is reflected by a mirror 16 to the prism 10 having spherical front and rear surfaces 21, 22. This prism acts as a collimator and forms a spectrum, after reflection again at the mirror 16, adjacent the linear exit slit 13. The curvature of the entrance slit compensates the astigmatism introduced by the Fery prism.