JPS6051702B2 - Color sorting plate making equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a color-selecting plate-making device that obtains two types of plate-making outputs, one for colored objects excluding black in a color document and one for black objects, and is particularly applicable to an electronic color mimeograph machine. There are some suitable methods.

Generally, when printing in color, three color originals are printed.
It is read by a photoelectric conversion element through two color separation filters, and the output from these is used to obtain a color separation signal. This can be done by creating a film, using this to form each printing plate, and overprinting each plate, but in mimeograph printing, when overprinting as described above, the difference between each plate is There is a large misalignment, making it impossible to obtain clear prints when overprinting using three printing plates, such as black, and black characters and thin black lines in particular have the disadvantage of being more difficult to read because their area is small. .

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

That is, when optically scanning a color original, the reflected light from the original surface is maximum when it is white, approximately zero when it is black, and intermediate value for colored objects.Therefore, when trying to obtain black, detection is required according to the reflected light. By inverting and amplifying the output, it is possible to obtain the maximum platemaking output for black, but in this case, the platemaking output for colored materials decreases, making it impossible to obtain prints with the same color tone as the original, and this must be compensated for. If you use a cut filter for a colored object in order to increase the plate-making output for a colored object, the resulting output will be the same as the output for black, and you will not be able to distinguish between them, so you will only be able to use a cut filter for black. It becomes impossible to cut. In view of the above,
In the present invention, reflected light from a document is received by two separate photoelectric conversion elements, and one of the photoelectric conversion elements provides a black cut output, and the other photoelectric conversion element provides a white transmission output. Based on these, it is an object of the present invention to provide a new color-selecting plate-making device that obtains a colored plate-making output from which black is removed and a black plate-making output.Embodiments of the present invention will be described below with reference to the drawings. .

In the figure, numerals 1 and 2 are photoelectric conversion elements that receive reflected light from the surface of the document. Element 1 has a black cut filter (for example, Kodak 47B filter (product name)) 3 disposed on its light receiving surface, and the reflected light is No output is obtained only when the color is black, and the element 2 is provided with a black and colored object cut filter, that is, a white transmission filter (for example, Hoya C-500 filter (trade name)) 4 on its light-receiving surface to prevent reflection. Output is obtained only when the light is white.

As shown in FIG. 2, the photoelectric conversion elements 1 and 2 are arranged as shown in FIG. A half mirror 1 is attached through a lens system 8 and a slit in a slit plate 9 at an inclination angle of, for example, 45 mm.
0, the transmitted light and the reflected light are made to enter the photoelectric conversion elements 1 and 2, respectively, or the half mirror 10 is omitted and the half mirror 10 is replaced with 2
Book glass fibers 11 and 12 are buried so that their one ends are in contact with each other, and photoelectric conversion elements 1 and 2 are arranged at the other ends. Reference numerals 13 and 14 designate DC inverting amplifiers to which outputs Sl and s2 from elements 1 and 2 are supplied, respectively, and invert amplified outputs of outputs Sl and 2, respectively, are obtained.

Reference numerals 15 and 16 denote first and second changeover switches that operate in conjunction with each other. The switch 15 has its fixed contact t1 connected to the output side of the amplifier 13, and its fixed contacts T2 and t3 connected to each other to connect the amplifier 1.
The switch 16 has its fixed contact T2 connected to the output side of the amplifier 13, and its fixed contacts Tl, t.
3 is an empty contact.

18 is an oscillator, 19 is a ring modulation circuit, and this modulation circuit 19 has diodes Dl and D2, and switches 15, which are supplied from this circuit to modulation input terminals 20 and 21;
A modulated output, that is, S3, in which the oscillation output V1 from the oscillator 18 is modulated according to the outputs S3 and S4 from the 16 movable contacts.
When only the oscillation output V1 is obtained, an output V2 of zero is obtained when only the output S4 is obtained, or when the outputs S3 and S4 are obtained simultaneously.

22 is a power amplifier whose output is applied to a discharge recording needle (not shown) to destroy the mimeograph paper by discharge.

Note that 23 is a level adjuster. Next, the operation of the above configuration will be explained.

First, the movable contacts T of the changeover switches 15 and 16. When switched to the fixed contact t1 side, only the output of the amplifier 13 is supplied to the modulation input terminal 20, and since the output of the amplifier 13 is obtained only when the document surface is black, the modulator 19
Output (2) is obtained only when the color is black, and based on this, a black mimeograph paper can be formed. Also, when the movable contacts (■) of the changeover switches 15, 16 are switched to the fixed contacts, the amplifiers 13, 1
Both of the four outputs are supplied to the modulation input terminals 20 and 21, and output is obtained from the amplifier 14 only when the document surface is black or colored. Therefore, when the document surface is black, the amplifier 13, 14, therefore, the modulated output V2 cannot be obtained, and the modulated output V2 is obtained only when the object is colored other than black.
2 is obtained, on the basis of which a mimeograph paper for colored objects can be formed.
Furthermore, the movable contacts T of the changeover switches 15 and 16.

When switched to the fixed contact side, the output of the amplifier 14 is supplied to the modulation input terminal 20, so that a normal monochrome copying paper can be formed. As described above, according to the present invention, the reflected light from the document surface is incident on the photoelectric conversion element through the black cut filter and the white transmission filter, respectively, and based on the inverted output, a black plate making output and a color plate making output are obtained. As a result, it is possible to obtain a mimeograph paper that shows only the black color in a color original, and a mimeograph paper for colored materials with the black part cut out, and when printing black, there is no need to overprint as in normal color printing. Therefore, it is possible to clearly print black characters, thin lines, etc., and is particularly suitable for two-color mimeograph printing of black and other colors.

Moreover, the configuration to obtain the above effect is extremely simple, as it only requires adding two photoelectric conversion elements each equipped with a black cut filter and a white transmission filter, two inverting amplifiers, and two changeover switches to a normal plate making device. There are some that have great characteristics such as: Next, the second aspect of the present invention
An example of this will be explained with reference to FIG. 4 and subsequent figures.

In this example, parts corresponding to those in FIGS. 1 to 3 are denoted by the same reference numerals, and detailed explanation thereof will be omitted, but photoelectric conversion elements 1,
2 is inside a cylinder 34 having a partition wall 33 in which through holes 31 and 32 are bored at a predetermined interval in the center, and its light-receiving surface faces the through holes 31 and 32 through filters 3 and 4, respectively. The through holes 31, 3 are buried with an insulating synthetic resin material 35 as shown in
On the opposite side of 2, a slit plate 39 having slits 37, 38 is disposed so that the slits face the centers of the through holes 31, 32, forming a light receiving section 40, and the slits 37, 38 follow the slits 37, 38. The photoelectric conversion elements 1 and 2 are arranged on a scanning line on a rotating drum (not shown), with the photoelectric conversion element 1 leading, for example.

Further, the magnification of the lens system 8 is set to a predetermined magnification (for example, the through holes 31, 3
When the distance between the through holes 31 and 32 is 6Tf0n, the distance between the through holes 31 and 32 is selected to be approximately 6 times), so that the distance between the through holes 31 and 32 when projected onto the rotating drum through the lens system is approximately 1T0Tt. being done. Further, a delay correction circuit 41 is provided after the inverting amplifier 13. An example of this circuit is composed of a diode D and a variable capacitor C interposed between the cathode side of the diode D and ground, and by changing the capacitance of the capacitor C, the output of the amplifier 13 is delayed by a predetermined time. let It is desirable that the delay time in this case is approximately equal to the delay time that occurs between the photoelectric conversion elements 1 and 2 when the photoelectric conversion elements 1 and 2 scan the same point on the rotating drum. Note that the interposition of the delay correction circuit 41 is arbitrary, and it suffices that the delay correction circuit 41 be installed at any position in the system of the photoelectric conversion element 1. Except for the above configuration, this embodiment has the same configuration as that of the first embodiment. According to the above configuration, the photoelectric conversion elements 1 and 2 and the inverting amplifier 13
, 14, a delay time occurs in the output obtained from the amplifier 14, but since a delay correction circuit 41 is interposed in the system of the photoelectric conversion element 1 that precedes in the scanning direction, the output obtained through this circuit 41 and the amplifier 14 Since the output is substantially synchronized with the output of Since there is no need to provide reflected light introduction means such as glass fiber, the configuration of the photoelectric conversion section can be simplified. In each of the above-mentioned embodiments, two changeover switches and a ring modulator are used, but as shown in FIG.
are supplied to the negative input terminal 46 and positive input terminal 47 of the positive AND circuit 45, respectively, and the output side of the inverting amplifier 13, the output side of the AND circuit 45, and the output side of the inverting amplifier 14 are respectively supplied to the selector switch 48. Even if the output obtained from the movable contact of the changeover switch 48 is connected to the fixed contacts Tl, t2, and t3 and is supplied as a control signal to the gate circuit 50 to which the oscillation output from the oscillator 49 is supplied, the same result as in the above example can be obtained. It goes without saying that effects can be obtained, and that the AND circuit can also be replaced with a negative OR circuit or an exclusive OR circuit. Furthermore, in each of the above-mentioned embodiments, the case where the output for black plate making and the output for color plate making are selectively obtained by changing the changeover switch has been explained. In the embodiment shown in FIG. 4, the modulator 1
Two sets of gate circuits 9 are provided, one of which is directly supplied with the output of the amplifier 13, and the other of which is supplied with the outputs of both amplifiers 13 and 14, respectively. In the case of the embodiment shown in FIG. 5, two sets of gate circuits 50 are provided. The output of the amplifier 13 is connected to one side and the OR circuit 45 is connected to the other side.
It is only necessary to supply the outputs of the respective outputs.

j Brief Description of the Drawings Figure 1 is a connection circuit diagram showing one embodiment of the device of the present invention, Figure 2 is a connection circuit diagram showing an embodiment of the device of the present invention;
3 and 3 are route maps showing a photoelectric conversion device, and FIGS. 4 and 5 are connection circuit diagrams showing other embodiments of the device of the present invention.

1 and 2 are photoelectric conversion elements, 3 is a black cut filter, 4 is a white transmission filter, 13 and 14 are inverting amplifiers, 19 is a modulator, 41 is a delay correction circuit, and 45 is a positive AND circuit.

Claims (1)

[Scope of Claims] 1. Light reflected from the document surface is incident on the first photoelectric conversion element via the black cut filter, and is incident on the second photoelectric conversion element via the white transmission filter, 1
The outputs of the photoelectric conversion elements and the second photoelectric conversion elements are respectively supplied to first and second inverting amplifiers, and an output for black plate making is obtained from the first inverting amplifier, and the outputs of the first and second inverting amplifiers are A color selection plate making device characterized in that when only the output of the second inverting amplifier is obtained, the output is supplied to a circuit that obtains the output, and an output for color plate making from which black is removed is obtained from the circuit. 2. The reflected light from the surface of the document wound around the rotating drum is transmitted to the first photoelectric conversion element, which has slits arranged in parallel in the scanning direction with respect to the rotating drum at predetermined intervals, and has a black cut filter on its light receiving surface, and a white photoelectric conversion element. The light is incident on a second photoelectric conversion element provided with a transmission filter through a lens system with a predetermined magnification, and the outputs of the first and second photoelectric conversion elements are supplied to first and second inverting amplifiers, respectively. , a delay correction circuit is interposed in the system of the photoelectric conversion elements in the first and second photoelectric conversion elements that precede the rotational direction of the rotating drum, and the output for black plate making from the first inverting amplifier is provided. An output for color plate making in which the outputs of the first and second inverting amplifiers are supplied to a circuit that obtains the output when only the output of the second inverting amplifier is obtained, and black color is removed from the circuit. A color-selecting plate-making device characterized in that it obtains.