JPH03210516A - 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 cylindrical 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 a lighting optical system state at the time of reading, a projecting lens system 11, a microfilm 12 held between pressing plate glasses, a condenser lens system 13, and a light source 15 are arranged on an optical axis and the cylindrical lens 14 is arranged out of the optical axis. At the time of printing, the lens 14 is inserted between the light source 15 and the lens system 13 on the optical axis to form an anamorphic lighting optical system. When a target is illuminated with high illuminance by inserting the lens 14 into the lens system 13 at the time of printing, the exposure speed can be increased. Consequently, the number of copies can be improved.

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 cylindrical convex lens is inserted into a condenser lens system to increase the illuminance and to increase exposure. 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 by the reflector 1, and condenses it by the condenser lens system 4 to illuminate it in a line. be done. The linearly illuminated image of the microfilm 5 is then formed and recorded in a linear form by a projection lens system 6 through a slit 7 onto a photosensitive drum 8 rotating at a speed VI shown by an arrow. At this time, the microfilm 5 moves at a speed V shown by the arrow.
Move upwards with o. That is, the microfilm 5 is moved at a speed Vo that takes into account the rotation speed VI of the photoreceptor drum 8 and the projection magnification, and projects an image onto the photoreceptor drum 8 with the slit direction perpendicular to the plane of the paper.

FIG. 4 is a sectional view showing the configuration of the optical system of a lens scan type micro reader printer during plinking, and the micro film 5 is fixed. and a light source 9 including a reflecting mirror arranged coaxially. The condenser lens system 10i3 and the projection lens system 6 move at a speed V as shown by the arrow.
Move upward with L to illuminate the microfilm 5 linearly. The image of the illuminated microfilm 5 is captured by the light source 9
The projection lens system 6, which moves upward at a speed VL as shown by the arrow in synchronization with the condenser lens system 10, projects and records the image through the slit 7 onto the photoreceptor drum 8, which rotates at a speed VI shown by the arrow. Ru. In this case as well, the photosensitive drum 8 moves at a rotational speed 1 of the photosensitive drum 8 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 illumination system for both is the same, with full-scale illumination when used as a reader and line illumination when used as a printer. Since priority is given to the illuminance ratio during the reader, it is not possible to improve efficiency even though the illumination range during the printer is small.If the illumination can be efficiently illuminated, the copying speed can be increased.

This invention has been made in view of these points, and when using a printer, it is possible to increase the exposure speed by inserting a cylindrical lens into the condenser lens system to increase the illumination intensity. Therefore, 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.

[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 a printer is used, anamorphic illumination is performed by inserting a cylindrical convex lens into the condenser lens system.

[Example] The following is a detailed explanation of the present invention based on the drawings.
The figure shows a 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. Condenser lens system 131
3 and a light source 15 are arranged on the optical axis. At this time, the cylindrical lens 14 remains off the optical axis.

Figure 1 CB) shows the state of the illumination optical system when used as a printer. When used as a printer, the cylindrical lens 14 is inserted on the optical axis between the light source 15 and the condenser lens system 13 to create an anamorphic illumination optical system. .

The reason why it is possible to increase the illuminance with such an anamorphic illumination system is because the condenser magnification in the direction perpendicular to the slit is made larger than in the slit direction by the cylindrical convex lens 14.

This point will be explained in detail below with reference to FIG. Second
FIG. 2(A) is an optical path diagram showing a light beam from an arbitrary point on the photoreceptor in the slit direction during reading, and FIG. 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 during printing.

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 at which the image is projected in the vertical direction of the slit is significantly smaller than that in the vertical direction of the slit.In other words, the illumination range is small, so 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 convex lens 14, 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 condenser lens system formed as described above is applied will be explained with reference to the drawings. FIG. 5 is an optical path diagram showing the configuration of a film scan type micro reader printer, in which the micro film 12 is illuminated by condensing illumination light from a light source 15 through a condenser lens system 13. The image of the irradiated microfilm 12 is reflected by the projection lens system 11 at the mirrors 16 and 17 as shown by the dashed line when the reader is used, and is projected onto the screen 18 for observation. In addition, when printing, the light is reflected by mirrors 19 and 20 and formed into an image on the photoreceptor drum 21, as shown by broken lines. At this time, the microfilm 12
As shown in FIG. 6, it is housed in a film carriage 22, the driving force of a motor 23 is transmitted to a scan clutch 25 via a belt 24, and a drive wire 2
6, it is configured to be scanned in the direction of the arrow.

The condenser lens system 13 is shown in FIG. 7(A).

As shown in (B), a cylindrical lens 14 is held in a lens holder 31, and is configured so that a binion 33 fixed to the output shaft of a motor 32 and a rack 34 mesh with each other. The cylindrical lens 14 can be moved onto the optical axis by moving the holder 31 in the right direction indicated by the arrow.

Therefore, from the reader state shown in FIGS. 7(A) and 7(B), the motor 32 is driven and the cylindrical lens 1 is
4 to the printer state shown in FIG. 1(B). Conversely, it is also possible to switch from the printer state to the reader state with the cylindrical lens removed.

In the above example, the switching of the cylindrical lens to the optical axis was explained using a sliding type that moves the cylindrical lens from side to side, but this may also be done by rotating the cylindrical lens in a turret type. Furthermore, although a film scan type micro reader printer has been described, it goes without saying that the present invention can be similarly applied 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 has a condenser lens system composed of an axially symmetrical spherical lens system used at the time of the reader, which has power in the direction perpendicular to the slit at the time of the printer. By inserting a cylindrical lens, the illuminance and illuminance ratio during reader operation can be obtained at the same level as with conventional illumination systems, and in addition, during printer operation, it is possible to perform anamorphic illumination that increases the condenser magnification in the vertical direction of the slit. This makes it possible to improve the efficiency of illumination and increase the exposure illuminance when printing, making it easy to increase the number of copies in a given time by increasing the exposure speed.

[Brief explanation of drawings]

1(A) and 1(B) are sectional views in the direction perpendicular to the slit and sectional views in the slit direction, showing the configuration of the illumination optical system for a micro-reader printer of the present invention when used as a printer; ) is an optical path diagram in the slit direction at the time of reader, Figure 2 (B) is an optical path diagram in the perpendicular direction to the slit, and Figure 2 (
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. A cross-sectional view showing the configuration of a reader/printer; FIG. 5 is an optical path diagram of a film scan type micro-reader/printer when reading
6 is a perspective view showing the film carriage shown in FIG. 5, and FIGS. 7(A) and 7(B) are a top view and a front view showing an example of the drive mechanism of the condenser lens system shown in FIG. 5. 11... Projection lens system 12... Micro film 13... Condenser lens system 14... Cylindrical convex lens

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 at the time of the reader is illuminated by a condenser lens system composed of an axially symmetrical lens system, and at the time of the printer, anamorphic illumination is achieved by inserting a cylindrical convex lens into the condenser lens system. An illumination optical system for a micro reader printer, which is characterized by performing the following. (2) Claim 1 characterized in that a cylindrical convex lens is inserted between the light source and the axially symmetrical condenser lens system.
Micro reader printer illumination optics as described.