JPS6026213B2 - Color sorting plate making equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a color-selecting plate-making machine that selectively obtains a specific color and a black plate in a color original, and is particularly suitable for application to an electronic color mimeograph machine. be.

Generally, when performing color printing, a color original is passed through three color separation filters to a photoelectric conversion element, and a color separation signal is obtained from the output from these filters. This is done by creating three color separation films for the yellow plate and the yellow plate, forming each printing plate, and overprinting each plate.In mimeograph printing, overprinting is performed as described above. As a result, there is a large discrepancy between each plate, and when overprinting using three printing plates, such as black, it is not possible to obtain clear prints, and black letters in particular are difficult to read because their area is small. It has its drawbacks.

Therefore, in order to print without overprinting black, it is only necessary to extract only the black part of the original, but currently colors such as red and blue are filtered using color filters or cut filters. Although it is easy to extract or cut only those colors using , it is impossible to cut black due to the principle of plate making.

In other words, when optically scanning a color original, the reflected light from the original surface is maximum when it is white, zero when it is black, and intermediate value for colored objects.Therefore, when trying to obtain black, the detection output is inverted according to the reflected light. If it is amplified, it is possible to obtain the maximum plate-making output for black, but in this case, the plate-making output for colored materials decreases, making it impossible to obtain prints with the same hue as the original, and for this reason If you use a cut filter for that colored object to increase the output, the resulting output will be the same as the output for black, and you will not be able to distinguish between them, so it is impossible to cut only black. It becomes possible. In view of the above, the present invention is such that at least when making a plate for a colored object, the black color is removed and the black plate is made separately.Examples of the present invention will be described below with reference to the drawings.

In the figure, 1 is a document surface wrapped around a rotating drum (not shown), and 2 is a scanning head that is driven to be transferred in a direction perpendicular to the rotational direction of the rotating drum.
It is comprised of a light source 3 that illuminates the document surface, and a photoelectric conversion device 5 that receives reflected light 4 from the light source on the document surface.

An example of the photoelectric conversion device 5 includes an optical system 6 including an objective lens, a slit plate 7, a half mirror 8 mounted at an inclination angle of, for example, 45 degrees, and this half mirror.
A part of the reflection hole from 8 is incident on the photomultiplier tube 10 through a specific color cut filter 9, and a part of the reflected light obtained by passing through the half mirror is directly incident on the photomultiplier tube 10, where the reflected light is black. It is composed of a photodiode 11 as a photoelectric conversion element whose output becomes zero only when . In this case, as the specific color cut filter 9, as shown in FIG. 16 are arranged in the 1/4 area of the frame board 13, and the remaining 1
The area '4 is formed with through holes 17, or as shown in FIG. 2B, a green filter 14, a red filter 16, a blue filter 16, and a through hole 17 are arranged in series. ,
Its position is changed by movement with a changeover switch 23, which will be described later. Reference numeral 21 denotes a DC inverting amplifier to which the output S from the photomultiplier tube 10 is supplied, and an inverted amplified output of the output S, that is, an output S2 representing a color that does not pass through the filter 9 and black is obtained.

The reason why an output representing black is obtained here is that in the case of black, the irradiated light from the light source 3 is absorbed and no reflected light 4 from the document surface is obtained, so the output S of the multiplier tube 10 is approximately This is because it becomes zero. 22 is an inverting DC amplifier similar to the amplifier 21, which receives the output S3 from the photodiode 11 and provides an output S4 only when the color is black.

23 and 24 are first and second switching switches that move relative to each other, and the switching switch 23 has its movable contact to connected to the amplifier 21.
On the output side of The movable contact to is connected to the output side of the amplifier 22, the fixed contact t4 is connected to the modulation circuit 31A, and the fixed contacts L to t2 and the like are empty contacts.

Reference numeral 26 denotes an AND circuit whose input side is connected to amplifiers 21 and 22, and which can obtain the power output only when outputs S2 and S4 are both obtained.

Reference numeral 27 designates a changeover switch that operates in conjunction with the changeover switches 23 and 24, with a movable contact to connected to the output side of the AND circuit 26, and fixed contacts t and 27 connected to the other modulation input terminal 31B of the modulation circuit 31, which are connected to each other. The fixed contacts t4 and t5 are connected to each other, and the fixed contacts t4 and t5 are empty contacts.

Note that 28 is a bell adjustment circuit. 30 is an oscillator, 31 is a modulation circuit, and this modulation circuit 31 includes a diode D,
, D2, and modulation input terminals 31A and 3 from this circuit.
Color selection signal S consisting of output S2 or S4 supplied to 1B
The oscillation output V from the oscillator 30 is modulated in accordance with the black signal S8 consisting of the signal S7 and the output flea.When only the modulated output, that is, the signal S7 is obtained, the oscillation output V, is zero when the signals S7 and S8 are obtained simultaneously. An output V2 is obtained.

Reference numeral 33 denotes a power amplifier, the output of which is applied to, for example, a discharge recording needle (not shown) to destroy the mimeograph paper by discharge.

The above is the configuration of one embodiment of the present invention. According to this configuration, when the movable contacts ``to'' of the changeover switches 23, 24, 27 are switched to the fixed contacts t, the filter 9 that moves with them rotates. For example, the green filter 14 faces the multiplier tube 10, and therefore, the multiplier tube 10 does not provide the output S only when the document surface 1 is red and black, and the amplifier 21 conversely outputs the output S2. On the other hand, since the output S4 is obtained from the amplifier 22 only when the document surface 1 is black, the output S4 of the AND circuit 26 is 0 when the document surface 1 is red, and 1 when the document surface 1 is black. Accordingly, the output V2 is obtained from the modulation circuit 31 only when the original surface 1 is red, so that a red mimeograph paper can be formed. Also, selector switches 23, 24, 2
When the movable contact t0 of 7 is switched to the fixed contact t (or t3) side, the red filter 15 of the filter 9 (or the blue filter 1
6) faces the multiplier tube 10, and as in the case described above, the modulation circuit 37 outputs V only when the document surface 1 is blue (or yellow).
2 can be bound, thus forming a blue (or yellow) mimeograph. Furthermore, the movable contacts t of the changeover switches 23, 24, 27
. When switched to the fixed contact side, the output of the logic neck circuit 26 is not coupled to the modulation circuit 31, and only the output S4 from the amplifier 22 is supplied to the modulation circuit 31. Output V2 is obtained only when 1 is black, thus making it possible to form a black mimeograph. When the movable contacts to of the changeover switches 23, 24, and 27 are fully switched to the contact t5 side, the through hole 17 of the filter 9 faces the extension tube 10, and the output of the amplifier 22 is Since the output is blocked, a normal monochrome mimeograph can be produced. As described above, according to the present invention, signals representing a specific color of the original and black are obtained from an inverting amplifier using a specific color cut filter, and a signal representing black is obtained from a separately provided photodiode. It is possible to obtain a mimeograph paper with the black part of the color document cut out, and a mimeograph paper that only shows the black color, and when printing black, there is no need to overprint as in normal color printing, and therefore black characters etc. can be clearly seen. It is suitable for use in color mimeograph printing as described above.

Although the above example describes the case where the specific color cut filters 9 are green, red, and blue, it is of course possible to cut colors other than the above example using other cut filters.

Also, the interlocking relationship between the changeover switches 23, 24, 27 and the specific color filter 9 is separated, and the fixed contacts of the changeover switches 23, 34, 27 are set to t3 and t4 so that they are switched only when obtaining black, thereby obtaining a specific color. In some cases, the filters 9 may be moved individually.

Furthermore, in the above example, the case where the present invention is applied to a mimeograph paper plate making machine has been explained, but as shown in FIG.
, the fixed contact t4 of the changeover switch 24 is connected to the gate circuit 42.
The gate circuit 41 is supplied with the inverted output of the output S5 of the AND circuit 26, and the gate circuit 42 is supplied with the circuit 2.
The present invention can be applied to other plate making machines other than the mimeograph paper plate making machine by controlling the gate circuits 41 and 42 to open respectively with the outputs S5 of 6 and using the outputs obtained from the gate circuits 41 and 42 as outputs for plate making. You can also do it.

[Brief explanation of the drawing]

Fig. 1 is a systematic connection diagram showing an embodiment of the present invention, Fig. 2A
and B are front views each showing an example of a cut filter applicable to the present invention. 1 is the document surface, 9 is a specific color cut filter, 10 is an optical multiplier, 11 is a photodiode, 21, 22 are inverting amplifiers, 23, 24, 27 are changeover switches, 26 is an AND circuit, 31 is modulation circuit. Boat Plan M Ship’s Figure 2 A Figure 2 B

Claims (1)

[Claims] 1 Reflected light from the original is incident on the first photoelectric conversion element via the specific color cut filter, and is also incident on the second photoelectric conversion element whose output is zero only when the reflected light is black, A first photoelectric conversion element in which the outputs of the first and second photoelectric conversion elements are coupled to each other via first and second inverting amplifiers, respectively.
and a second changeover switch as well as an AND circuit, and the color selection output obtained through the first and second changeover switches, and the black signal output obtained from the AND circuit. A color-selecting plate-making device characterized by selectively obtaining specific color and black plate-making outputs cut by a specific color cut filter.