Transmitting and copying machine

A transmitting and copying machine comprising an optical system on the copying side having an image forming lens for guiding original-scanning reflected light onto a photosensitive material to form an image thereon, an optical system on the transmitting side having an optical axis biased in a main scanning direction, and a fixed mirror for refracting the optical axis of the optical system on the transmitting side such that the optical axis passes in front of the image forming lens to be guided onto the solid scanning element via the reading lens. The reading lens has a small maximum half image angle and the fixed mirror has a small reflecting surface. Then, the optical system on the transmitting side can be inserted very easily in the machine.

Description of the Invention: 
The present invention relates to a transmitting and copying machine having 
a function of transmitting to a distance an image of an original converted 
into electric signals, and a function of copying such an image. 
An object of the present invention is to provide a copying machine of an 
ordinary construction to which a function of transmitting an image of an 
original to a distance is added. 
Another object of the present invention is to minimize a maximum half image 
angle of a reading lens in an optical system on the transmitting side. 
Still another object of the present invention is to minimize the reflecting 
surface of a fixed mirror whereby the optical axis of the optical system 
on the transmitting side is bent. 
A further object of the present invention is to eliminate troubles due to 
stray light in an optical system on the copying side and optical system on 
the transmitting side.

In order to simultaneously effect the transmitting of an image of an 
original and the copying of the same in a conventional transmitting and 
copying machine of this kind, an optical system on the transmitting side 
and an optical system on the copying side had to be separately formed. 
Conventional transmitting and copying machines of this kind include a one 
as shown in FIG. 1 in which such optical systems have a part in common. In 
this transmitting and copying machine, a light source 3 and a first mirror 
4 whereby the light reflected on an original 1 is refracted are disposed 
under a table 2 on which the original 1 is placed, such that the light 
source 3 and first mirror 4 can be reciprocated along the table 2. A 
second mirror 5 whereby the light reflected on the first mirror 4 is 
further refracted is disposed such that the second mirror 5 can be 
reciprocated at a speed 1/2 time that of the first mirror in the same 
direction in which the first mirror is moved. An optical system 8 on the 
copying side having an image forming lens 7 whereby the light reflected on 
the second mirror 5 is formed into a life size image on a photosensitive 
material 6, and an optical system 11 on the transmitting side having a 
reading lens 10 whereby the light reflected on the second mirror 5 is 
formed into a reduced image on a solid scanning element 9 are disposed 
adjacent to each other with respect to an auxiliary scanning direction (a 
direction in which the light source 3 and first mirror 4 are moved). 
In such a structure, however, light passages in the optical systems 8, 11 
are different and the area of the second mirror 5 must be increased. When 
these light passages are brought close to each other, the image forming 
lens 7 and reading lens 10 must be brought very close to each other. This 
causes difficulty in regulating the image forming lens 7, reading lens 10 
and solid scanning element 9. Moreover, the photosensitive material 6 is 
actually disposed at the back of the image forming lens 7 and a scanning 
light passage is extended in front of the image forming lens 7. Then, it 
becomes difficult to install the solid scanning element 9 and reading lens 
10 in the optical system 11. There is another conventional transmitting 
and copying machine as shown in FIG. 2, in which a ready-made scanning 
optical system to be installed does not need to be modified. In this 
machine, the axis of an optical system 8 on the copying side and that of 
an optical system 11 on the transmitting side are biased in a main 
scanning direction (a direction of the width of an original 1). However, 
in order to prevent the light passage in the optical system 11 from being 
superposed on that in the optical system 8, an irregular light passage as 
shown in FIG. 3 has to be provided, or an image of an original has to be 
cross-read. In such an optical system, a reading lens 10 of an extremely 
large image angle is required. 
The rays shown in the drawings after FIG. 3 are envelope curves of 
effective image forming light. 
There is another conventional optical system as shown in FIG. 4, which is 
provided with a fixed mirror 12, and a reading lens 10 and a solid 
scanning element 9 on the cross-reading side. In this case, however, the 
reflecting surface of the fixed mirror 12 and a maximum half image angle 
.theta..degree. of the reading lens 10 must be large. 
Now, a first embodiment of the present invention will be described with 
reference to FIGS. 5-11. In the description, the same parts as shown in 
FIGS. 1-4 will be designated by the same reference numerals and the 
description thereof will be omitted. 
An optical system 8 on the copying side is formed, which has an optical 
axis .phi..sub.1 formed by the axes of a surface 13 of an original 1 and a 
photosensitive surface 14 of a photosensitive material 6. An image forming 
lens 7 is disposed in the central point of the optical axis .phi..sub.1. 
The image forming lens 7 is an in-mirror type life size image forming 
lens, which consists of a lens 15 and a mirror 16. A fixed mirror 16a is 
disposed between the image forming lens 7 and photosensitive material 6. 
An optical axis .phi..sub.2 of an optical system 11 on the transmitting 
side is provided such that the axis .phi..sub.2 is biased by a length l in 
a main scanning direction (a direction of the width of the surface 13 of 
original 1) with respect to the original 1. A solid scanning element 9 and 
a reading lens 10 are tentatively disposed on the optical axis 
.phi..sub.2, and a fixed mirror 12 is disposed, as it is inclined at 
45.degree., between the reading lens 10 and a second mirror 5 and in the 
vicinity of the image forming lens 7. The fixed mirror 12 causes the 
optical axis .phi..sub.2 to pass in front of the image forming lens 7 so 
as to be bent at 90.degree. toward a side plate 17. The solid scanning 
element 9 and reading lens 10 are disposed on the optical axis .phi..sub.2 
bent by the fixed mirror 12. The focal distance of the reading lens 10 is 
set such that a passage n of the light reflected on the fixed mirror 12 
and extending up to the surface of the solid scanning element 9 almost 
reaches the vicinity of the side plate 17 of a copying machine body. 
Assuming that an image angle of the image forming lens 7 in this surface 
is .alpha. as shown in a side elevational view in FIG. 6, an image angle 
of the reading lens 10 is also set at .alpha. (FIG. 7) so that a scanning 
system consisting of the first and second mirrors 4, 5 are used in common. 
As shown in a side elevational view in FIG. 7, the light reflected on the 
fixed mirror 12 advances diagonally and downwardly through an opening, 
which is immediately before the image forming lens 7, of a sheltering 
plate 7, whereby the light advancing from the optical system 8 on the 
copying side into the image forming lens 7 and the light outgoing from the 
image forming lens 7 are separated from each other, and enters the reading 
lens 10 perpendicularly provided in the side plate 17. 
In a light passage formed in the above-described manner, a maximum half 
image angle .theta. of the reading lens 10 can be minimized and a lens of 
an extremely large image angle is not required. In addition, the length of 
a reflecting surface of the fixed mirror 12 can be minimized. This may be 
clearly understood from FIG. 8 in which an optical system in the first 
embodiment of the present invention is illustrated in contrast to that in 
a transmitting and copying machine shown in FIG. 4. FIG. 8a illustrates an 
optical system in the embodiment of the present invention shown in FIG. 5, 
while FIG. 8b illustrates an optical system in a conventional transmitting 
and copying machine. The optical systems shown in FIGS. 8a, 8b are 
identical when the optical system 11 on the transmitting side is operated 
without the fixed mirror 12. However, in the optical system shown in FIG. 
8b, the reflecting surface of the fixed mirror 12 is long and projected 
into the optical system 8 on the copying side. In order to shorten the 
reflecting surface of the fixed mirror 12, the mirror may be moved a 
little back to a position 12' as shown in FIG. 8b but it may then be 
collided with a photosensitive material 6. Then, this is not practical. In 
order to prevent the fixed mirror 12 from being projected into the optical 
system 8 on the copying side, it is necessary that the length l of an 
optical axis .phi..sub.2 of the optical system 11 on the transmitting side 
be changed to l' with respect to an optical axis .phi..sub.1 (l'&gt;l) as 
shown in FIG. 8c. After all, a maximum half image angle 
.theta..sub..degree. is greater than that .theta. in the present 
invention. Consequently, a reading lens 10 of a large image angle is 
required or an ordinary reading lens 10 cannot be applied. In other words, 
a reading lens 10 of a special design has to be used. When a light passage 
is set as in the optical system according to the present invention, a 
maximum half image angle .theta. of a reading lens 11 and the length of 
reflecting surface of a fixed mirror 12 can be minimized. 
The light passage can be selectively set by a sensor board unit 19 
consisting of a solid scanning element 9 and a reading lens 10 and a lens 
CCD unit 21 consisting of a lens holder unit 20, which are detachably 
provided on a side plate 17 as shown in FIG. 9. The lens CCD unit 21 may 
be directly mounted on the side plate 17, and it may be integrally formed 
with an optical housing 22 to maintain the precision of optical 
measurements. Since the optical axis .phi..sub.2 of the reading lens 10 is 
kept perpendicular with respect to the side plate 17, the light passage 
can be easily set even when the reading lens 10, solid scanning element 9 
and sensor board unit 19 are formed separately. In any case, the optical 
and electric systems can be controlled at a side portion of the machine. 
In addition, the surface of a copied image is never affected by flaring 
light since the light reflected on the fixed mirror 12 advances downwardly 
through the opening in the sheltering plate 18. 
The spectral sensitivity of the photosensitive material 6 is not always the 
same as that of the solid scanning element 9. Thus, the fixed mirror 12 
may be used as an interference mirror while suitably regulating the 
spectral reflection factor thereof in accordance with the spectral 
sensitivity of the solid scanning element 9, to control the 
photosensitivities of both of them to suitable levels. A part to be read 
is asymmetrically disposed with respect to the optical axis .phi..sub.2 of 
the reading lens 10 and, consequently, an asymmetrical shading correction 
is required. In order to conduct an asymmetrical shading correction, it 
may be necessary to provide a shading correction plate 23 immediately 
before the fixed mirror 12 as shown in FIG. 10. Such a shading correction 
can be carried out by not only the shading correction plate 23 but also an 
electric means. In order to perfectly prevent stray light from occurring 
during a copying operation, a shutter 24 may be provided in front of the 
fixed mirror 12 as shown in FIG. 11. This shutter 24 may be omitted when a 
copied image is not affected by stray light. 
A printer, such as CRT (not shown) may be inserted as a copying means in 
this kind of machine so that the machine permits both the recording of a 
copied image, which can be effected by a conventional machine as well, and 
the recording of a digital image. The insertion of such a printer also 
allows an electrical exchange of information between a plurality of the 
same type of machines. When the CCD unit 22 is omitted, this machine can 
be used in the same manner as a conventional copying machine, or the 
machine may have another function as necessary. 
FIGS. 12 and 13 show a second embodiment of the present invention, in which 
the transmitting and scanning of a surface 13 of an original divided into 
two is carried out by two sets of symmetrically disposed optical systems 
11 on the transmitting side. In this arrangement, the density of main 
scanning lines with respect to the same main scanning width is doubled. 
When the density of main scanning lines are the same, the main scanning 
width can be doubled. 
The transmitting and copying machine according to the present invention is 
provided as mentioned above with a fixed mirror whereby the optical axis 
of an optical system on the transmitting side, which is biased with 
respect to that of an optical system on the copying side, is bent as it 
passes in front of an image forming lens; and a reading lens and a solid 
scanning element on the optical axis thus bent. Therefore, a maximum half 
image angle of the reading lens and the reflecting surface of the fixed 
mirror can be minimized. In addition, the optical system on the 
transmitting side can be practiceably inserted without modifying the 
optical system on the copying side and the neighbouring parts.