JPS617834A - Lighting device for slit exposure - Google Patents

Abstract

PURPOSE:To adjust finely the illuminance on an irradiated surface with stage glass fitted, by providing a specified cut in a main reflector and forming plural tongue pieces, and deforming the tongue pieces independently of one another. CONSTITUTION:Lengthwise cuts 9 and cuts 8 perpendicular to them are provided at the bulb back surface side of the main reflector 7 along a bulb 2 to form plural tongue pieces 7a-7e. Those tongue pieces 7a-7e are deformed independently of one another to change the reflection direction of light from light emitting segments 11a-11e, thereby adjusting the illuminance. In this case, the tongue pieces 7a-7e are at the opposite side of an original 6, so the illuminance on the irradiated surface is adjusted with the stage glass 5 fitted. Further, the tongue pieces 7a-7e are fractionized into 7a-7e, so a fine illuminance adjustment is made.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a slit exposure illumination device for illuminating the surface of a document in a projection printing apparatus or the like.

Configuration of conventional example and its problems Conventionally, this type of slit exposure illumination device has been equipped with a light distribution adjustment mechanism for adjusting the illuminance distribution.
Two types are known, as shown in Figures A and B.

The basic structure of these models is to provide a light-shielding plate 3 between a linear tube 2 provided along the main reflector 1 and the original 6. The rotation angle of the light shielding plate 30 is changed on the front side of the tube No. 1, and the 10th
In the case of FIG. B, the amount of protrusion of the light shielding plate 3 is also changed. In FIGS. 10A and 10B, 4 indicates a sub-reflector and 6 indicates a stage glass.

However, in all of these methods, the stage glass 5 had to be removed once to adjust the illuminance distribution, and it was not possible to adjust the illuminance distribution while monitoring it. In addition, these devices have a structure in which the light shielding plate 3 is divided into several parts that are relatively far from the tube 2.
Even when a portion of the light shielding plate 3 is adjusted, the illuminance distribution cannot be finely adjusted, and therefore it is difficult to obtain a predetermined illuminance distribution.

OBJECTS OF THE INVENTION The present invention provides a slit exposure illumination device that can monitor and adjust the illuminance distribution while maintaining the positional relationship with the irradiated surface in the actual state of use.

Structure of the Invention The present invention provides a slit exposure illumination for document illumination, in which a main reflector and a linear tube provided along the main reflector are arranged so that the illuminance on the exposure surface has a predetermined distribution. In the device, a plurality of tongues are formed by providing a plurality of notches in the back side portion of the bulb of the main reflector, and the tongues are independent of each other due to the notches and are deformable. It is characterized by a slit exposure illumination device.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a side sectional view of a slit exposure illumination device which is an embodiment of the present invention, and FIG. 2 is a perspective view of the same essential parts.

As shown in FIG. 1, a linear tube 2 is provided along a main reflector 7 having an elliptical or parabolic surface. Main reflector 7
A stage glass 6 is provided on the front side of the stage. In the same book, 4 is the sub-reflector.

6 indicates a manuscript.

As shown in FIG. 2, the main reflector 7 is provided with a plurality of notches 8 on the back side of the tube in a direction perpendicular to its length.
Further, a plurality of notches 9 are provided in the length direction of the tongue piece 7a.

'yb, 7c, 7d, and 7e are formed. These tongue pieces 7a to 7e can be freely deformed independently of each other in any direction by the notches 8.9.

The tube 2 has a plurality of light emitting segments 11a, 11b, 11c inside the glass tube 10 along the tube axis direction.

A filament 11 having 11d and 116 is provided. And tongue pieces 7a, 7b, 7c, 7
(1.

7e is light emitting segment 11&, 11kl, 110+11
(N is provided corresponding to the rear of i and 11e, respectively.

With the above structure, by adjusting the angle of one or more of the tongues 71L to 7e, for example in the front-back direction, with the connecting portion 12 as the center, each light-emitting segment can be adjusted. It is possible to change the direction of reflection of the light emitted rearward from 11a to 116, and it is possible to make the illuminance on the six surfaces of the original document a predetermined distribution. Moreover, in this device, the illuminance distribution adjustment point is closer to the tube 2 than in conventional devices, so the illuminance distribution corresponding to each light emitting segment) 11a to 116 can be finely adjusted, and the original 6 In order to appropriately adjust the tongue pieces 7a to 7e at the opposite position, it is possible to adjust the illuminance distribution while keeping the stage glass 5 in the actual state of use.

Next, a specific example of the present invention will be explained.

In the structure shown in FIGS. 1 and 2, a JK75V150W halogen light bulb is used as the bulb 2. In this halogen light bulb, the outer diameter of the glass tube 1o is 6mm, and the total length of the lamp is 25811mm. The number of light emitting segments of the filament 11 is six. A bending tube 2 is provided along the main reflector 7,
While keeping the stage glass 6 in the actual state of use, the tongue piece 7N is moved 1 and 8 times, the tongue piece 7b is o, 6IIIB, the tongue piece 7c is O''l (deformed f), and the tongue piece 7d is -1,0. When adjusting the tab 7e by deforming it by 1.5B, the illuminance on the document surface was as shown in the curved line in Figure 3 before the adjustment, but after the adjustment, the original was as shown in the curve ■ in the same figure. This is the surface illuminance.

The illuminance distribution has become uniform. Here, before adjustment, the tongues 7a to 7e are all in the position shown by the solid line in FIG. 4, and after adjustment, for example, they are deformed by a distance l to the position shown by the two-dot chain line in the same figure. . In the above, distances with a negative sign in front of them are when the distance is deformed in the direction of the arrow ■, and distances without a negative sign are when the distance is deformed in the direction of the arrow 0.

FIGS. 6 to 9 show how the document surface illuminance changes when each tongue piece is deformed individually. That is, FIG. 6 shows only the tongue piece 7a.

Figure 6 shows only the tongue piece 7b, Figure 7 shows only the tongue piece 7C,
FIG. 8 shows the illumination on the document surface when only the tongue 7d is changed, and FIG. 9 shows the illuminance on the document surface when only the tongue 7e is changed.

This shows that the solid line state before the adjustment changed to the broken line and the dashed-dot line state after the adjustment.

In addition, when experiments were conducted using filaments in which the number of light-emitting segments was changed, results similar to those described above were obtained.

Furthermore, although the above description has been made regarding the case where the illuminance distribution is made uniform, the present invention can be implemented in the same way when obtaining an illuminance distribution where both ends are raised from the center.

As described in detail, when the apparatus of the present invention is used, the main reflector and the linear tube provided along the main reflector distribute the illuminance on the exposure surface to a predetermined distribution. A slit exposure illumination device for document illumination arranged as shown in FIG. Because
By adjusting the illuminance distribution using the tongue piece of the main reflector located on the back side of the tube, it is possible to perform one-time adjustment work while maintaining the positional relationship with the irradiated surface in the actual state of use. Furthermore, unlike conventional devices, the device of the present invention adjusts the illuminance distribution using the main reflector adjacent to the bulb, making it possible to make fine adjustments and thus easily obtaining a predetermined illuminance distribution. .

[Brief explanation of drawings]

FIG. 1 is a side sectional view of a slit exposure illumination device that is an embodiment of the present invention, FIG. 2 is a perspective view of the same main part, and FIG. 3 is a diagram showing an example of adjusting the illuminance distribution using the same device. FIG. 4 is a sectional view showing a modified example of the tongue piece in the same device, and FIGS. 6 to 9
The figure also shows how the illuminance distribution changes with respect to the amount of deformation of each tongue, and Figures 1O and 1B are side sectional views showing a conventional slit exposure illumination device. 2...Tube, 7...Main reflector, ya, 7
b. Ryo Q, 7d, 7θ... tongue piece, 8,9.
・・・・・・Incision depth. 10...Glass tube, 11...Filament, 111L. 11b, 110, 11 (1,111 --- Light emitting segment. 4 agents Patent attorney Toshio Nakao 1 person Figure 1 Figure 3 Figure 1 Figure 5 Figure 6 Lighting - j < l Distance from center D of document surface (mat) Figure 9 Illumination area 1 Distance from center of document surface to 5 (m, %) 1st
Figure 0 (A) CB)

Claims (1)

[Claims] A slit exposure illumination device for document illumination, in which a main reflector and a linear tube provided along the main reflector are arranged so that illuminance on an exposure surface has a predetermined distribution, Slit exposure characterized in that a plurality of tongues are formed by providing a plurality of notches in the back side portion of the bulb of the main reflector, and the tongues are deformable independently of each other due to the notches. lighting equipment.