JPH03210517A - Lighting optical system for microreader/printer - Google Patents

Abstract

PURPOSE:To improve an exposure speed and to increase the number of copies for a fixed time by inserting a toroidal lens having power into a condenser lens system at the time of reading and in the vertical direction of a slit at the time of printing. CONSTITUTION:In the state of the lighting optical system at the time of reading, a projection lens system 11, a microfilm 12 held between pressing plate glasses, the condenser lens system 13 formed by lenses 131 to 133 in an axially symmetrical lens system, and a light source 15 are arranged on an optical axis and a toroidal lens 133' is arranged out of the optical axis. At the time of printing, the lens 133' is inserted into the optical axis instead of the condenser lens 133 arranged on the light source 15 side to form an anamorphic lighting optical system 13'. When the toroidal lens 133' having strong power in the vertical direction of the slit is inserted into the condenser lens system 13 to illuminate a target with high illuminance at the time of printing, the exposure speed can be increased. Consequently, the number of copies can be increased.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to the illumination system of a micro reader printer, and more specifically, when using a printer, a toroidal lens is inserted into a condenser lens system to increase the illuminance and expose the printer. This invention relates to an illumination optical system for micro reader printers that improves speed and significantly increases the number of copies.

[Prior Art] A conventional micro reader printer will be explained with reference to the drawings. Figure 3 shows the micro-photograph of the film scan method.
This is a cross-sectional view showing the configuration of the optical system of a reader/printer, in which the microfilm 5 reflects the illumination light from the light source 2 directly and with the reflecting mirror 1, and condenses it with the condenser lens system 4 to illuminate it in a line. be done. The image illuminated in a line on the microfilm 5 is recorded in a line through a slit 7 by a projection lens system 6 onto a photoreceptor drum 8 rotating at a speed V indicated by an arrow. . At this time, the microfilm 5 moves at a speed v indicated by an arrow.
Move upwards with O. That is, the film 5 is moved at a speed VO that takes into account the rotational speed VI of the photoreceptor 8 and the projection magnification,
An image whose slit direction is perpendicular to the plane of the paper is projected onto the photoreceptor 8.

FIG. 4 is a sectional view showing the configuration of the optical system of a lens scan type micro reader printer when printing, and the micro film 5 is fixed. And all the light including one reflecting mirror! 9. A condenser lens system 10i5 and a projection lens system 6 are arranged coaxially, and each moves upward at a speed VL as shown by the arrow to linearly scan and illuminate the microfilm 5. The image of the illuminated microfilm 5 is rotated through a slit 7 at a speed VI shown by the arrow by a projection lens system 6 that moves upward at a speed VL as shown by the arrow in synchronization with the light source 9 and the condenser lens system 10. The image is projected onto the photosensitive drum 8 and recorded. In this case as well, the projection lens 6 and the light source 9
．． The condenser lens system 10 has a rotation speed VI of the photoreceptor 8.
It moves at a speed VL that takes into account the projection magnification.

[Problems to be Solved by the Invention] By the way, in the above-mentioned film scan type and lens scan type micro reader printers,
The lighting system for both is the same, with full-surface lighting when reading and line lighting when printing. Furthermore, since priority is given to the illuminance ratio during reading, there is no attempt to improve efficiency even though the illumination range during printing is small.

If this can be efficiently illuminated, it will be possible to increase the copying speed.

This invention was made in view of these points, and when using a printer, by replacing one toroidal lens with strong power in the direction perpendicular to the slit in the condenser lens system, the illuminance is increased and the exposure speed is increased. It is an object of the present invention to provide an illumination optical system for a micro reader printer that can increase the number of copies and therefore increase the number of copies.

[Means for Solving the Problems] In the present invention, in the illumination optical system of a micro reader printer that performs slit exposure using a lens scan method or a film scan method at the time of printing, the illumination optical system at the time of reader is an axially symmetrical lens system. This is an illumination optical system for a micro reader printer, characterized in that illumination is performed by a condenser lens system configured, and when the printer is used, anamorphic illumination is performed by inserting a toroidal lens into the condenser lens system.

[Example J] Hereinafter, the present invention will be described in detail based on the drawings. 1st
The figure shows a cross-sectional view of the optical system of a film scan type micro reader printer, and FIG. 1(A) shows the state of the illumination optical system during reading. That is, in order from the left enlargement side, the projection lens system 11. Microfilm sandwiched between pressure plate glass 12. Axisymmetric lens system lens 1
31, 13g, 13. A condenser lens system 13 and a light source 15 are arranged on the optical axis. At this time, toroidal lens 13. remains off the optical axis.

FIG. 1(B) shows the state of the illumination optical system when used as a printer. When used as a printer, a toroidal lens 13,'' is inserted on the optical axis in place of the condenser lens 13m on the light source 15 side to create an anamorphic illumination optical system 13'. That is.

Such an anamorphic condenser lens system 13'
It is possible to increase the illuminance by increasing the condenser magnification in the vertical direction of the slit with a 13 m'
This is because it was made larger than the slit direction.

This point will be explained in detail below with reference to FIG. Second
Figure (A) is an optical path diagram showing the light flux from an arbitrary point on the photoreceptor in the direction of the slit opened during reader, and Figure 2 (B)
is an optical path diagram in the direction perpendicular to the slit. Also, Figure 2 (C
) shows an optical path diagram in the direction perpendicular to the slit when printing. The optical path diagram in the slit direction when printing is the same as FIG. 2(B).

If you compare the light flux emitted from the on-axis point in Figure 2 (A) with the light flux in Figure 2 (C), it is clear that the light flux shown in Figure 2 (C) has a larger condenser magnification. .

This is because the angle of view for projecting one image in the vertical direction of the slit is significantly smaller than in the vertical direction of the slit.In other words, since the illumination range is small, there is no need to consider the illuminance ratio in the vertical direction of the slit. This is because if the focal length of the condenser lens system 13' is reduced by inserting the lens 133', the distance to the pupil of the projection lens system 11 is constant, so naturally the condenser magnification increases.

Next, a micro reader printer to which the anamorphic illumination optical system formed as described above is applied will be explained with reference to the drawings.

Figure 5 shows a film scan type micro reader.
In this side sectional view showing the configuration of the printer, a microfilm 12 converts illumination light from a light source 15 into a condenser lens system 1.
3 or 13' and irradiates the entire image or a line. This irradiated image is reflected by the projection lens system 11 and mirrors 16 and 17 at the time of the reader, as shown by the dashed line, and projected onto the screen 18 for observation. Further, when printing, the light is reflected by mirrors 19 and 20 and formed into an image on the surface of the photoreceptor 21, as shown by the broken line. At this time, the microfilm 12 is stored in the film carriage 22 as shown in the sixth factor, and the driving force of the motor 23 is transmitted to the scan clutch 25 via the belt 24, and the drive wire 26 engaged with this is configured to be scanned in the direction.

As shown in FIG. 7, the condenser lens system 13.13' includes an optical axis symmetrical lens t3m and a toroidal lens 133' held in a lens holder 31, and a motor 32.
Binion 33 and lens holder 3 fixed to the output shaft of
The first rack 34 is configured to mesh with the other, and the lens holder 31 is configured to be moved in the direction shown by the arrow by rotation of the motor 32. Therefore, the seventh
The motor 32 is driven from the reader state shown in the figure to remove the toroidal lens 13. ', it is possible to change to an anamorphic illumination optical system 13' for a printer, and conversely, it is possible to change to an ordinary illumination optical system 13 with an optical axis symmetrical lens for a reader.

In addition to ensuring a sufficient illuminance ratio during reading,
When used as a printer, the number of copies can be increased by improving the illuminance ratio.

In the above example, a sliding mechanism was described, but it is of course possible to form the lens holder 31 so that it can rotate in a turret type.

In this embodiment, a film scan type micro reader printer has been described, but it is of course applicable to a lens scan type micro reader printer.

[Effects of the Invention] As explained above, the illumination system for a micro reader printer of the present invention applies power in the direction perpendicular to the slit during the printer to a condenser lens system composed of a 63-axis symmetrical spherical lens system used at the time of the reader. By inserting a toroidal lens, the illuminance and illuminance ratio during reader operation can be obtained at the same level as with conventional illumination systems, while at the same time, during printer operation, it is possible to perform anamorphic illumination that increases the condenser magnification in the vertical direction of the slit. Therefore, it is possible to improve the efficiency of illumination and increase the exposure illuminance during printing, and it is therefore possible to easily increase the number of copies in a given time by increasing the exposure speed.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view in the vertical direction of the slit during reading and a cross-sectional view in the vertical direction of the slit during printing, showing the structure of the illumination optical system for a micro reader printer of the present invention. Fig. 2 (B) is an optical path diagram in the direction perpendicular to the slit, and Fig. 2 (B) is an optical path diagram in the slit direction when
C) is an optical path diagram in the vertical direction of the slit during printing, Figure 3 is a sectional view showing the configuration of a conventional film scan type micro reader printer, and Figure 4 is a conventional lens scan type micro reader printer. FIG. 1 is a sectional view showing the configuration of a reader/printer. Figure 5 shows a film scan type micro reader.
Optical path diagram when the printer is used as a reader and when the printer is used. Fig. 6 is a perspective view showing the film carriage shown in Fig. 5. Figs. 7 (A) and (B) show the drive mechanism of the condenser lens system shown in Fig. 5. FIG. 2 is a top view and a front view. 11... Projection lens system 12... Micro film 13... Condenser lens system

Claims (2)

[Claims] (1) Micro-photography that performs slit exposure using the lens scan method or film scan method when printing.
In the illumination optical system of a reader/printer, the illumination optical system for the reader is illuminated by a condenser lens system composed of an axially symmetrical lens system, and for the printer, anamorphic illumination is achieved by inserting a toroidal lens into the condenser lens system. An illumination optical system for a micro reader printer, which is characterized by performing the following. (2) The illumination optical system for a micro-reader printer according to claim 1, wherein the illumination optical system is made into an anamorphic illumination optical system by replacing at least one spherical lens and toroidal lens of the condenser lens system.