JPH0394555U

JPH0394555U -

Info

Publication number: JPH0394555U
Application number: JP238790U
Authority: JP
Priority date: 1990-01-17
Filing date: 1990-01-17
Publication date: 1991-09-26

Description

[Brief explanation of drawings]

第１図は本考案の実施例の変倍光学系の構成を
示す断面図、第２図〜第５図は夫々従来の複写機
の変倍光学系の構成を示す断面図である。１……コンタクトガラス、２……露光々源、３
……第１ミラー、４……第１スキヤナ、５……第
２ミラー、６……第３ミラー、７……第２スキヤ
ナ、８……結像レンズ、９……第４ミラー、１０
……第５ミラー、１１……第３ミラーユニツト、
１２……第６ミラー、１３……第７ミラー、１４
……第４ミラーユニツト、１５……第８ミラー、
１６……感光体。 FIG. 1 is a sectional view showing the configuration of a variable magnification optical system according to an embodiment of the present invention, and FIGS. 2 to 5 are sectional views showing the configuration of a variable magnification optical system of a conventional copying machine. 1...Contact glass, 2...Exposure source, 3
...First mirror, 4...First scanner, 5...Second mirror, 6...Third mirror, 7...Second scanner, 8...Imaging lens, 9...Fourth mirror, 10
...Fifth mirror, 11...Third mirror unit,
12...6th mirror, 13...7th mirror, 14
...4th mirror unit, 15...8th mirror,
16...Photoreceptor.

Claims

[Claims for Utility Model Registration] A first scanner 4 carrying a light source 2 and a first mirror 3 that illuminate the image surface of a document placed on a contact glass 1; A second scanner 7 carrying a second mirror 5 and a third mirror 6 is located on the document side of the imaging lens 8.
The imaging lens 8 has a mirror on the side of the photoreceptor that changes the direction of the light flux to a direction opposite to the scanning direction and makes the light beam enter the photoreceptor, and synchronizes the first scanner 4 and the second scanner 7 so that the direction of the light beam is 1:1 in the scanning direction. A copying machine that performs exposure scanning by moving at a speed ratio of 1/2, moves the lens 8 when changing magnification, and also moves some of the mirrors to correct the optical path length of the lens 8 on the original side and the photoreceptor side. In the variable magnification optical system, the optical system includes a third mirror unit 11 on the photoreceptor side of the imaging lens 8, which carries a fourth mirror 9 and a fifth mirror 10 for changing the direction of the light beam to the direction opposite to the scanning direction. , a sixth mirror 12 and a seventh mirror 1 for returning the direction of the light beam from the fifth mirror 10 to the scanning direction.
3, and an eighth mirror 15 that bends the light beam from the seventh mirror 13 so as to project it onto the photoreceptor 16. During reduction, the imaging lens 8 and the third mirror unit 11 are , during magnification, the imaging lens 8 and the fourth mirror unit 14
A variable magnification optical system for a copying machine, characterized in that the optical path length is corrected by moving the optical path length.