JPH0410271B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application of the Invention] The present invention relates to an image receiving device that receives a projected image from a projection section, and more particularly to an image receiving device that can freely read images.

[Prior art]

In recent years, as image reading devices have become more multi-functional, image reading devices that can read projected images of microfilm, slide film, etc. in addition to the image of a document scanned by the image reading device are being considered.

FIGS. 11 and 12 are cross-sectional views showing conventional examples of the above-mentioned image reading device.

101 is a document table glass fixed to the main body A of the apparatus, 1
Reference numeral 02 denotes a movable image information reading unit disposed on the lower surface side of the document table glass. The unit 102
are a document illumination lamp 121, a short-focus imaging element array 122 (product name: Selfoc), and a solid-state imaging element array 1.
23 (contact type licensor), etc., and is guided by a guide rail by a drive mechanism (not shown) and reciprocated at a predetermined speed along the lower surface of the document platen glass 101 from a home position on the left side of the glass to the right side. When it reaches the end of the round trip, it returns to its home position and moves again.

When reading an enlarged projected image of a slide film, etc., a reflecting mirror 104 and a Fresnel lens 105 are arranged above the document table glass as shown in FIG. An enlarged projected image of the slide film is formed from the device 6 on the focusing plate 107 via the reflecting mirror 104. After adjusting the slide projection device 6 to accurately focus on the focus plate 107, pull out the focus plate 107 as shown in FIG. 12 so that the light beam reaches the image information reading unit 102, and then The above projection image information is read by scanning the image information reading unit 102 with the light off.

Note that when a self-occurring lens array is used for the imaging element array 122 as in this example, it is necessary to convert the projection light into a parallel light beam, and the Fresnel lens 105 has a directional effect on the light beam that spreads in the projection direction. It is used to hold. (13th
The figure shows the state of the light flux in a system excluding the reflection mirror 104. ) In the case of a copying machine, the output signal read in this way is sent to a laser beam printer, inkjet printer, etc. built into the image reading device or provided separately, and printed, and in the case of an image reader, it is sent to a display device or The data is sent to a storage device or the like. In the case of facsimile, the information is sent to the receiving device by wire or wirelessly.

In the configuration described above, if the short focus imaging element array 122 is used as in this example to make the image information reading unit 102 of the main body A smaller and lighter, or to simplify the mechanism, even if the focus plate 1
07 itself is made as thin as possible, and the position of the focusing plate 107 is set to the short focus imaging element array (hereinafter referred to as SLA) 1.
Even if the depth of focus is set to within the depth of focus of 22, due to its characteristics, the amount of light on the imaging plane becomes highly uneven, resulting in a disadvantage that a uniform image cannot be obtained.

This tendency occurs when the imaging lens is fully moved, but it is particularly noticeable in SLA.

Next, the reason for this will be explained based on the characteristics of SLA.

When an SLA is used as an imaging lens, the imaging relationship of one short focus imaging element (hereinafter referred to as SL) is as shown in FIG. 14. Generally, the degree of bulkiness m of SLA is expressed as m=Xo/P...Xo: field of view radius P: pitch of SL.

FIG. 15 shows the relationship between the degree of overhang m and the unevenness in light amount (pitch unevenness) on the image plane. As is clear from this figure, the greater the degree of overlap, the smaller the unevenness in the amount of light on the imaging plane.

However, the effective focal point number on the magnifying side of the projection lens
When F _NO becomes dark and the divergence angle k of the projected light flux in Fig. 16 becomes smaller than the viewing angle θ of the lens, the off-axis light flux is eclipsed from the lens, and the field of view radius becomes substantially
Xo becomes smaller. As is clear from the above equation, this results in a reduction in the degree of bulk m itself. In other words, this leads to an increase in unevenness in the amount of light on the imaging plane.

Furthermore, detailed reasons are described in Utility Model Application No. 103985/1985 (Kokai No. 10662/1988).

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned drawbacks and provide an image reading device that can stably read a projected image without unevenness in the amount of light.

[Summary of the invention]

In order to achieve the above object, the present invention provides an image receiving device having an image receiving optical member for receiving a projected image from a projection unit which is detachably attached to a document glass of an image reading device. It has a cover member that covers the image-receiving optical member provided in between, and when the image-receiving device is attached to an image reading device and the cover member is removed, the image-receiving optical member comes into close contact with the document table glass. It is.

[Embodiments of the invention]

1 to 8 are diagrams showing embodiments of the present invention.

FIG. 1 is a perspective view showing an embodiment of the image receiving device according to the present invention in an open state, FIG. 2 is a cross-sectional view of the main part showing the upper frame in the closed state, and FIG. 3 is a cross-sectional view of the main part showing the upper frame in the open state. It is a diagram. FIG. 4 is a sectional view of a main part showing the lower cover in a closed state, and FIG. 5 is a cross-sectional view thereof. FIG. 6 is a sectional view of a main part showing a state in which the lower cover is pulled out (the state shown in FIG. 1), and FIG. 7 is a cross-sectional view thereof.

In FIGS. 1 to 7, reference numeral 4 denotes a plate-shaped optical image receiving member, the surface of which is in contact with the document table glass 101 is a transmission-diffusion surface, and the opposite surface is a Fresnel lens (hereinafter referred to simply as a Fresnel plate). call). As shown in FIGS. 5 and 7, the Fresnel board 4 has stepped portions 4a on both sides, a Fresnel support plate 5 that supports the Fresnel board, and a frame shaped frame having an opening that is one size smaller than the Fresnel board. When the lower cover 7 is closed, the Fresnel plate is supported in such a manner that it is sandwiched between the lower frame 2 and the lower frame 2 that restricts its upward movement. The Fresnel support plate 5 is shown in Figures 4 and 6.
As shown in the figure, it is supported by the lower frame 2 in a vertically movable manner, that is, movably in the direction of the light beam, by means of a stepped screw 6. 7 is a lower cover for protecting the Fresnel plate from scratches and dirt when the image receiving device is removed from the image reading device, and on both sides there are sliding members 8 for guiding the movement of the lower cover.
is fixed, and the sliding member 8 and the side plate tip 7a of the lower cover 7 lift the Fresnel plate 4 together with the Fresnel support plate 5 to the guide rail portion 2a of the lower frame 2, as shown in FIG. It is inserted in the state. The lower cover 7 is 7a as shown in FIG.
It can be pulled out until the part touches part 2b. At this time, the tip of the portion 7a is located below the bent portion 5a of the Fresnel support plate 5. This prevents the engagement between 7a and 5a from breaking down when the lower cover 7 is inserted. 7b is a knob for putting in and taking out the lower cover 7.

In Figure 8a, Figure 8b and Figure 1, 3
is a reflective mirror, which is attached to an upper frame 1 having an opening on the reflective surface side of the reflective mirror; one lower end of the reflective mirror 3 is connected to a hook portion 3 fixed to the upper frame 1;
04 and the elastic member 305, the upper two points are supported at three points by the U-shaped leaf spring 301. Furthermore, the mounting angle of the reflecting mirror 3 can be adjusted using two setscrews 302 attached to the leaf spring 301. Since this adjustment side is elastically biased by a leaf spring, no wobbling occurs. 303 is a nut for fixing the set screw 302. FIG. 8b shows a view seen from arrow A in FIG. 8a.

In FIGS. 1 and 3, hollow cylindrical fulcrum dowels 19 are provided at both ends of one side of the lower frame 2.
lower hinge members 18a, 18b having a, 19b
is fixed. In addition, in the upper frame 1,
A pair of upper hinge members 15a and 15b having holes that fit into the outer surfaces of the fulcrum dowels 19a and 19b are provided with a reflective mirror in between, and the upper frame 1
and the lower frame 2 are these fulcrum dowels 19a, 1
They are rotatably connected around 9b.

20a and 20b are stays for maintaining the angle of the upper frame 1 and lower frame 2 in the released state, and one end of each stay is connected to the upper hinge member 15.
It is rotatably attached to fulcrum pins 21a (not shown) and 21b fixedly attached to the lower frame a and 15b, and slide pins 22a and 22b are fixed to the other end of the lower frame. It slides along the elongated holes of guide rails 23a and 23b provided on the sides.

The holes of the fulcrum dowels 19a, 19b have torsion bars 17a, 17b inserted through them, and the pins 16 provided on the upper hinge members 15a, 15b.
A and 16b are attached to the lower frame, thereby biasing the reflection mirror 3 and the Fresnel plate 4 in a direction that increases the angle formed between them.

2C is a pin hole for positioning with the main body of the image forming apparatus. Also, 2d is the rubber foot of the lower frame, 7
C is a Delrin foot that improves the slipperiness of the lower cover.

Numeral 24 is a locking pawl for holding the upper frame 1 and lower frame 2 in a closed state, and the locking mechanism can be understood in more detail from Japanese Utility Model No. 168750/1983.

FIG. 9 shows a part of an image reading device equipped with an image forming section to which an image receiving device according to the present invention can be attached and detached. A guide line 51 is provided to match the outer shape of the . The mounting operation can be carried out smoothly with this guide line for mounting.

FIG. 10 shows an image reading device equipped with an image receiving device for receiving a projected image, seen from the left side. 40 is the upper cover of the image receiving device, and 41 is a cushioning material made of a soft rubber material provided at the corner of the image reading device. It is. Reference numeral 103 denotes a document pressure plate of the image forming apparatus.

Next, the operation of using such an image receiving apparatus will be explained.

When the image receiving device is not in use, the image receiving section is protected from external damage, dust, etc. by covering the upper and lower parts with a cover member, as shown in FIG.

When using the image receiving device attached to an image reading device, set the image receiving device on the document table of the image reading device in a predetermined positional relationship, open the upper frame, and then press the knob 7b of the lower cover 7.
Pinch and pull out the lower cover 7. In conjunction with this opening operation of the lower cover, the Fresnel support plate 5 supporting the Fresnel plate 4 is dislodged along the sliding member 8 of the lower cover, and the Fresnel plate is lowered together as shown in FIG.
As shown in FIG. 7, it is brought into close contact with the document table glass 101. Therefore, if the focus of the projected image from the projector 6 guided toward the Fresnel plate by the reflecting mirror 3 is set on the image receiving section, especially on the diffusing surface of the Fresnel plate, the reading device of the image forming apparatus The state is the same as when a normal original is placed.

In other words, in an image reading device that reads a document,
Since the reading optical system inside the apparatus is provided with the original position as a reference, by focusing the projected image on the original position, the projected image can be read accurately.

Further, since the image receiving section is in planar contact with the document table, there is no possibility of positional shift.

Furthermore, if the lower cover 7 is pushed in from the state shown in FIG. 6 to the left in the figure, the tip 7C of the lower cover will slip under the bent portion 5a of the Fresnel support plate 5 and scoop up the Fresnel plate 4 together with the Fresnel support plate. The state shown in FIGS. 4 and 5 can be easily returned to. Therefore, since the Fresnel plate 4 is housed between the lower frame and the lower cover of the projection image receiver, once the upper frame is closed, the main body can be easily removed without worrying about being affected by external damage or dust. You can take it on and off and carry it around.

FIGS. 17 and 18 show other embodiments of the present invention.

In the figure, reference numeral 61 denotes an axle having a round shaft 63, which is fixed to the four corners of the Fresnel plate 4. 57 is a round shaft 58
It is fixed to the lower frame 2 using an axle with a holder. 6
0 is a link connecting the round shafts 63 and 58, and the Fresnel plate 4 is swingably suspended from the lower frame 2.

62 is a torsion coil spring with one end connected to 57a,
The other end is attached to the shaft 63 and acts in the direction of pressing the Fresnel plate 4 onto the document table glass 101.

8 are fixed to both sides of the lower cover 7 and are swingably fitted into the square-shaped guide portions of the lower frame 2.
It is a sliding member for inserting and removing the lower cover in the direction A←-→, and the part 8a is the lower part 60 of the link 60.
It is in a position where it makes contact with a.

Reference numeral 64 denotes a bending portion which is fixed to the lower frame 2 and regulates wobbling of the Fresnel plate 4 in the B←-→ direction.

In the above configuration, FIG. 17 shows a state in which the lower cover 7 is inserted into the lower frame 2, and the 60a section of the link 60 rides on the 8a section, so the Fresnel plate is attached to the lower frame 2 and the lower cover 7. stored in between.

FIG. 18 shows the state in which the lower cover is pulled out, and since the link 60a section is separated from the section 8a, the Fresnel plate 4 is brought into close contact with the document table glass by the torsion coil spring 62. The spring, which is the elastic member, further improves the close contact relationship, which is preferable.

In this modification, a torsion coil spring 62 is provided to improve adhesion, but it is obvious that this may be omitted and the Fresnel board may be brought into close contact with the document table glass by its own weight.

When the lower cover is pushed in again from the state shown in FIG. 18, the parts 8b slip under the part 60a of the link 60 and push it up, causing the Fresnel plate 4 to move away from the platen glass, and the lower frame 2 and the lower cover 7 to be moved again. It is stored between.

As described above, the embodiments of the present invention utilize the sliding member of the cover, but it is preferable to move the image receiving section up and down by engaging the cover itself, since this allows the device to be made smaller and lower in cost. .

However, the present invention is not limited to the above embodiments, and the image receiving member and the cover may be connected by a wire and the image receiving member may be moved by the opening/closing operation of the cover, or a micro switch may be provided in the moving path of the image receiving member. The image receiving member may be moved by driving a solenoid or the like using a signal from the microswitch.

〔Effect of the invention〕

As explained above, in the present invention, since the image receiving member comes into close contact with the document table glass by removing the cover member that covers the image receiving member, the image receiving member can be reliably moved to a desired position even during use. The image forming position does not shift during use. In particular, since the image receiving member moves and contacts the document table of the image reading device in a flat manner, stable reading operations can be performed in an image reading device that reads ordinary documents. Furthermore, when not in use, the image receiving member is reliably protected by the cover member.

As described above, according to the image receiving device of the present invention, while having a high protection effect for the image receiving member, it is possible to eliminate the trouble of focus adjustment when attached to the reading body to be used, and the reading operation becomes more stable. .

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an embodiment of the image receiving device according to the present invention in an open state, FIG. 2 is a sectional view of a main part showing the upper frame in a closed state, and FIG. 3 shows the open state of FIG. 2. FIG. 4 is a cross-sectional view of the main part showing the lower cover in a closed state, and FIG. 5 is a cross-sectional view of FIG. 4. Fig. 6 is a cross-sectional view of the main part showing the state in which the cover is pulled out, Fig. 7 is a cross-sectional view of Fig. 6, Fig. 8 a,
FIG. 8b is a view showing the support part of the mirror, FIG. 9 is a perspective view of essential parts of an image reading device to which an image receiving device according to the present invention can be attached and detached, and FIG. 10 is a state in which the image receiving device is attached to the image reading device. Figure 11 showing
12 are cross-sectional views showing a conventional image receiving device, FIGS. 13, 14, 15, and 16 are explanatory diagrams for the present invention, and FIGS. 17 and 18 are sectional views showing the conventional image receiving device. It is a figure which shows another Example. 4: Fresnel plate (plate-shaped optical image receiving member),
5: Fresnel support, 7: cover member, 101: document table glass, 6: projection device, 102: document abutting index which also serves as a positioning plate of the projected image receiving device.

Claims (1)

[Scope of Claims] 1. In an image receiving device having an image receiving optical member that receives a projected image from a projection unit that is detachably attached to a document table glass of an image reading device, an image receiving device provided between the image receiving optical member and the document table glass. The image receiving device has a cover member that covers the image receiving optical member, and when the image receiving device is attached to an image reading device and the cover member is removed, the image receiving optical member comes into close contact with a document table glass. 2. The image receiving device according to claim 1, wherein the image receiving optical member has a Fresnel lens section.