JPS62116066A - Apparatus for converting color image display into electric signal - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for converting color image displays into electrical signals.

When transmitting images over long distances, the image to be transmitted is scanned by a device capable of converting the brightness of one pixel into a modulated electrical signal with a predetermined resolution for each pixel. When transmitting and receiving color images, a preferred method is to separate the color images into several colors. Color filters sequentially separate each color from the picture and each then generates an electrical signal. The receiver receives the respective signals and is subsequently caused to manage the reproduction of each of the assigned colors in turn.

The scanning is thus accomplished in as many steps as the number of colors selected for separation. In addition to color separation and color reproduction, this allows for a device that is generally less disjunctive than that required for black/self-portraits. Similarly, each color signal has the same characteristics as the black/self-portrait signal and may use the same communication channel, eg, a telephone line.

Similarly, in situations other than long-distance transmission of color images, there are devices that convert the representation of color images into electrical signals. For example, there are devices that are very similar to transmitters and receivers for long-distance transmission, but used locally on or based on electroplates or other printed media. There are devices that produce electrical plates or stencils using electrical signals generated based on images in devices that can be considered picture transmitters.

It is also possible to form the image signal so as to obtain a non-permanent image representation on the display.

Such an image display can be used for long-distance transmission or for local information, checking or editing. As is known, such an image display can be obtained using a television camera feeding a signal to a motor. However, the capacity of simple transmission lines such as telephone lines is insufficient for such signals, and in many such cases lower frequencies are used to create and transmit the signal, which is then stored in memory. Preferably recorded.

This signal is then converted to a higher frequency shape.

applied to the monitor. In order to create a transmission signal, an image transmitter configured for this purpose is required.

When separating colors, it is common to use various color filters in front of a scanning device that moves across the picture. The color filter consists of the same dimensions as the image surface used for scanning in such cases.

This results in relatively large color filters, and the costs are not negligible since they have to be manufactured with great precision. Additionally, where there are non-uniformities on the surface of the color filter, signals are generated that result in incorrect image display.

It is an object of the invention to provide a compact device for color separation in terms of signal formation and regeneration which reduces the cost of color filters compared to the case in prior devices and largely eliminates the risk of false signals due to non-uniformities within the color filters. There is a particular thing.

Yet another object of the invention is to provide an apparatus for color separation that allows the formation of color image signals using a continuous method that can be controlled in different ways to suit the different intended uses. There is a particular thing.

The figure shows an embodiment of the invention, which relates to an image transmitter that can be used for long-distance image transmission or for forming images for other purposes such as electroplating.

As FIG. 1 shows, the image transmitter comprises a casing 1, an illumination device 2 provided inside it, a picture (image) holder 3 arranged according to the invention, a mirror 5, an objective lens 6, a picture It consists of a scanning device 7 with a window 8 and a row scanner 9 and a motor 10, and a support beam 11 along which the mirror 5, objective lens 6 and scanning device 7 are mounted, the mirror 12 being rotatable by means of a hinge 13. installed on. In addition to the lighting device 2, the exterior of the casing includes a projection window 14, a keyboard 15, an electronic unit 16, and 1. An electronic display 17 is provided.

The lighting device 2 is hinged and can be lifted. Below it is a circular opening 18 into which the socket 4 (see FIG. 1) on the picture holder 3 can be inserted. In addition, the picture holder 3 has a picture window 19 which is placed in the light path from the lighting device 2 when the picture holder with its socket is positioned in the opening 18 and the lighting device 2 is in its lowered position. The optical path continues downwards towards the mirror 5 where it is deflected by the mirror 5 through the objective 6 towards the scanning device 7 . However, as shown in FIG. 1, the optical path can also be deflected towards the projection window 14 by raising the mirror 12.

When using the picture transmitter, a picture inserted into the picture holder 3 is projected by light from the illumination device 2 through the mirror 5 and the objective lens 6 onto the picture window 8 of the scanning device 7. It is then scanned by a column scanner 9 a number of times determined by the color separation to produce an electrical signal. This signal can be transmitted to a receiver or used in other ways for image reproduction.

The first simplified embodiment of the scanning device 7 shown in FIG. 1 is shown enlarged and in more detail in FIG. The row scanner 9 consists of a longitudinal extension which is movable along a guide 20 by means of a motor. The motor 1o and the guide 20 form a frame 21 having an opening 22 in which the column scanner 9 can be moved and generally displaying a pictorial (image) surface.
supported within. The image to be scanned is picture holder 3
It consists of a projection within the aperture 22 of the actual film image 4 within. This projection is achieved when the light from the illumination device 2 passes through the mirror 5 and through the objective lens 6 as described above. The picture is thus projected in such a way that the focal plane is located in the aperture 22 at the level of the row scanning member 23 on the row scanner 9. The column scanning member consists of a column of photosensitive elements which can be caused by electronic control to emit a continuous electrical signal along the column of elements, so that a line of the image is scanned. . As the column scanner moves on the guide 20, the image is scanned line by line until it is completely scanned.

The result is a modulated electrical signal that represents all of the imaging devices in the image, the resolution of which depends on the size and separation of the photosensitive elements along the column scanner 9 and also with respect to the scanning speed along the column scanner. It is determined by the moving speed, in other words, by the scanning line density.

Each photosensitive element emits a signal, the magnitude of which depends only on the intensity of the light incident on the element, without any indication of color. For technical reasons, the sensitivity of the light intensity of different colors varies and it also varies in relation to the human eye's perception of the luminance of different colors, but these conditions also reduce the signal indicative of color. It cannot be used to create.

As mentioned in the preamble, instead the image must be separated into different colors using color filters and the image must be scanned color by color. A minimum of three colors are required,
All colors and shades of colors can be created by mixing three colors if these three colors are properly placed with each other for technical color synchronization.

Furthermore, separation into three or more colors also occurs. In color printing, it is common to perform black separation printing corresponding to black and white signals. This kind of printing is called four-color printing.

Since the color filter is used for color separation and does not distort the perception of color, it is preferred to place the color filter close to the scanning device 7 when the image is viewed through the mirror 12 in the picture window 14. According to the invention, each color filter consists of a narrow plate 25 inserted into a strip 26 whose mounting on the row scanner 9 can be seen in FIG.

The color filter plates 25 follow the row scanner during scanning when they are mounted in order on the row scanner.

Each color filter should be approximately the same width as the photosensitive element in plane 23, which is only the width of one line. However, it is appropriate for the plate to have a somewhat greater width for handling purposes. This is not easy to handle, and the mounting accuracy of the plate may be low. The length should of course be the same as the length of one row of photosensitive elements.

The required color filter is attached to the strip 26 as shown.
can be integrated into the switching device so that the filter does not have to be handled separately. In this case, one possibility is to provide a color filter plate having several areas, each of which has one of said colors. By placing the plates at different locations within the strip 26, different areas can be placed in front of the array of photosensitive elements. Optionally, the switching device can be arranged, for example, as a “nosepiece” device.

The type of invention shown in FIG. 2 represents the simplest embodiment in which the color filters are removed and continuously inserted by hand. Other types that accommodate switching devices that can be automatic are more highly developed embodiments. A similarly more highly developed version is shown in FIG. 3 and described below.

As shown in FIG. 3, the scanning device 7 (the numbers used in FIGS. 1 and 2 are also used for common parts in FIG. 3) has a column scanner 9 movable along its guide 20. Contains. However, the second guide means 30 is provided in front of the row scanner 9, ie on the side on which the light beam from the projection device enters. carriage 3
1 , the guide means 30 support a plate 32 that is parallel to the light-sensitive elements of the column scanner 9 . Opening 3
3, the plate 32 has a number of color filters 3
4 is supported. Seven color filters are shown here. As noted, at least three filters are required to obtain the desired color separation.

In this case the device is made flexible by providing three filters for the separation of the positive image and three filters for the separation of the negative image, in addition to one aperture 33.
is left behind to create a black and white signal. It is intended for thermal printing of black and white images and four color printing.

In addition, a drive 35,36 for the carriage 31 is provided so that the device can be moved back and forth along the guide means 30.
Contains. The guide means 30 includes a screw 35;
The screw 35 is driven by a second motor 36 that meshes with a thread (not shown) on the carriage 31 and is housed in the drive device.

The guide 2 along with the filter 34 along the guide means 30
0 and the drives for moving the column scanner 9 along the color separation carriage 31 are arranged in a special coordinated drive sequence.

This is accomplished by controlling the rotation of motors 10 and 36. As is known, electric motors are available of the stepping motor type, which can be driven according to complex rotational patterns, usually under computer control. Such a motor is available for this scanning device and for this embodiment must be arranged at least for coordinated control of the two carriage devices. How this is accomplished is known to those skilled in the art and need not be further explained here.

However, the control sequence will now be explained. 1st
In the format, an image is scanned completely in a number of complete sequences corresponding to the number of colors from which this image is to be separated. In such a case the control sequence is plate 3
2, the column scanner 9 is placed directly in front of the photo-sensing element of the column scanner during the entire sequence and is adapted to follow the column scanner 9 as it moves over the surface of the image with a specific color filter 34 following along it. There is. During the next movement of the row scanner 9 over the surface of the image, in order to match the next color, the plate 32 is moved in the same way with the row scanner, but then moved, so that the color filter 34 of the method sequentially adjusts its light. Followed by a column scanner placed directly in front of the sensing element. The resulting signal sequence is thus divided into a number of subsequences, each of which in turn represents a complete representation of the entire image corresponding to one of the various separation colors.

Using another type of control sequence, the column scanner 9 first scans single lines or alternating small groups of lines across the image for the display of one color, thereby causing the corresponding color filter 34
is placed directly in front of the column scanner. The color separation plate is then moved to a column scanner 9 in which the next color filter 34 scans the same line or group of lines previously scanned for the first color.
positioned directly in front of the In this method, the same pixel, preferably a single line, is successively scanned as many times as the picture is to be separated by successive movements of the color filter in relation to the column scanner.

Once all colors have been displayed, the column scanner is moved to scan the next line following the same pattern. therefore,
The resulting signal is synthesized from subsequences representing small segments of the image, such as scan lines. Each subsection is sequentially divided into the number of scan sequences needed to represent all the separated colors.

For the latter control sequence, the drive line is such that the column scanner drive element using motor 10 maintains the column scanner in the various scanning positions, while the color separator drive element using motor 36 maintains all intended colors. A moving color filter must be placed in front of the column scanner 9 to be scanned. The motor 10 then moves the column scanner one step and the motor 36 adjusts the column scanner to the new position to achieve a new filter movement for scanning the next color sequence to the new initial position of the color separation. Move the device.

As mentioned, seven different color separation possibilities are provided. Three color filters for the positive image, three color filters for the negative image, and the possibility of forming a black and white signal.

The apparatus for moving the color separation carriage is arranged to accommodate four different scanning options:

1) Color separation of positive color image into three colors. In this case, the drive moves a color separation carriage with three color filters for the positive image in sequence in front of the row scanner.

2) Color separation to create three color signals and one black and white signal for positive color images, such as to create electroplates for four-color printing.

3) Separation into three colors for shade color images.

4) Separation of four colors for shade color images.

For the apparatus described above, control means for the coordinated movement of the column scanner and color filter plate must be arranged to switch when changes are made to the separation among the four different relationships described above.

The filters directed to the color separation of the positive image in the first case are sequentially moved to the front of the column scanner, in the second case the positions for the black-white signals are also included in the motion sequence and in the third case the color separation of the negative image. Three color filters for separation are moved, and in addition to the last-mentioned filter in the fourth case, positions for the formation of black-white signals are also included.

When using a device with a scanning device as shown in FIG. 2, the starting position of the row scanner 9 is at one edge of the opening 22. Once the appropriate image 4 has been selected and inserted into the picture holder 3, the picture holder is placed under the illumination device 2 and aligned using the projection window 14 until the desired adjustment is made. The mirror 12 is then lowered and the image is then projected into the aperture 22 by a focal plane in the plane 23 of the photosensitive element.

The order in which the colors are displayed in the scanning signal is determined in such a way that image reproduction at the receiver can be accomplished in conjunction with scanning at the transmitter. For the first scan, the filter for the first selected color is inserted into the strip 26 (FIG. 2) and the zero color filter plate 2 in which the scanning sequence is carried out.
5 is then swapped to the next color and the next scan is performed.

The sequence is repeated as described until all colors, three or more, have been displayed.

The manner in which the embodiment shown in FIG. 3 is used has been made clear above by the description of how the row scanner and color separator drives are arranged in a special control sequence. The scanning by the control sequence described first is mainly the first one.
Same as described above for the embodiment. The only essential difference is that the changing device for color filters appears to be an automatic device for changing the color filters when the picture is scanned in the number of complete sequences required for color separation. At the receiving end, the processing of the signal is no different from that seen in the first embodiment. The entire surface of the picture is formed in several stages, whereby the colors are added to one another in sequence to create a complete color image.

In an automatic embodiment of the device, it can switch between the various described control sequence options and filter selections as appropriate.

With other control sequences, you have a pixel-by-pixel structure with all colors displayed.

Other reception methods are required. Therefore, as for reception, it is the case that each pixel, preferably a single line, is generated individually with different colors being added in sequence to create a complete pixel. Thereafter, the next pixel or line is formed after the last pixel is regenerated until image regeneration is achieved at the receiver.

The type of scan sequence chosen determines the type of receiver that should be used. For the first type of scanning sequence a mostly black and white receiver can be used and the addition of color can be accomplished after reception. however,
Similarly, a modified black and white receiver is used;
The only necessary change in that case is that the complete signal sequence is registered using different colors. For registration of photosensitive materials using a light beam, this can be easily done using a color filter changer. For reception with the second scanning sequence, the receiver must be leveled to follow the same control cycle, which requires larger changes than a black-and-white receiver.

On the other hand, this control sequence allows greater precision in the reproduction. Since all colors are registered line by line, very good accuracy in the positioning of the various color representations for the various lines can easily be achieved.

However, using the control sequence mentioned at the beginning, greater difficulties are encountered in achieving such positional coincidence since the scanning and reproducing device has to be moved several times synchronously over the image surface. Due to the last described control sequence, the last mentioned embodiment as shown in FIG. 3 is therefore the most highly developed and, for a given application, represents the functionally most advantageous technique.

Using the invention, each color filter simply consists of a narrow plate, the length of which corresponds to the height of the projected image. As the color filter plate follows along the column scanner, its light sensing elements are not moved along the surface of the color filter. The narrow central part of the plate needs to be exactly right with respect to light refraction and color. There is therefore no risk of the column scanner passing through dirty areas, which can occur if a large plate relative to the fixed plate of the column scanner is used according to conventional methods.

Furthermore, the possibility to achieve very high precision in image reproduction is achieved using the most advanced embodiment as shown in FIG. 3 along with the last mentioned control sequence. In addition to the previously mentioned advantages, the phenomenon of surface size of monochromatic filters is an additional and equally appreciable advantage of the present invention.

The form of the invention depends on the requirements of the device in which it is to be used. If the received signals are used to produce printing means such as multiple color-separated electroplates or stencils, three or four complete color-separated signals are transmitted. In such cases, the simplest form can likewise be used by changing the means of the one-color filter plate. However, this method is very fast and error free if automatic equipment is used. For the case where color photographic images are produced directly in the receiving device, the accuracy will be improved by a better determination of the color separated images if the second control sequence is applied by successive construction of images column by column for all colors. is increased by In such cases automatic equipment must be used. This is also the case when the signal can be produced by the memory for display on a display. The colors on the cathode ray tube display are produced in such a way that the last-mentioned control sequence is most suitable.

As mentioned in the preamble, the invention can also be applied to scanning devices other than image transmitters.

In such cases it may have a different structure than that shown, adapted to the intended device and likewise without departing from the spirit of the invention. For example, a column scanner described by one row of photosensitive elements along a scan line may be replaced by a point scanner in which the scan point is moved along the scan line and there to the next scan line, performing a collinear scan. You can also do it. The use of such a principle system does not change the device according to the invention since the color filters may in that case also extend longitudinally along the line. Third
In the embodiment of the device for automatically changing color filters, as shown in the figure, two separate drive devices are described, one for the column scanner and the other for the color filters, which devices move these parts in a predetermined pattern. Drive in a manner coordinated by. However, the device can be arranged such that a single drive is provided, but the color filters are connected to the drive in such a way that they can be moved in relation to the drive. This means that when scanning is carried out using special color filters, said filters are fixedly connected to the drive for the column scanner, while
When the color filters are changed, a special changing device means that the mounting for the color filters results in relative movement between the device and the row scanner. The same scanning pattern can be achieved in this way as well when using another drive.

[Brief explanation of drawings]

1 is a perspective view of an image transmitter, FIG. 2 is a perspective view of a first embodiment of a scanning device used in the image transmitter and arranged according to the invention, and FIG. 3 is a perspective view of a second embodiment of the scanning device. It is a perspective view showing an example. In the figure, 7 is a scanning device, 9 is a row scanner, 10 is a motor, 20 is a guide, 22 is an opening, 25 is a narrow plate (color filter), 26 is a strip, 30 is a second guide means,
32 is a plate. 33 is an opening, 34 is a color filter, and 36 is a second motor. Patent applicant Victor Hasselblad Aktivolag - to,

Claims (10)

[Claims] (1) a station for displaying an image in the image plane, at least one light-sensing element arranged to produce an electrical signal indicative of the brightness of the image in the scanned area, and a number of scanning lines covering the image plane; a moving mechanism for moving the photosensitive element across the image plane in a pattern consisting of a plurality of electrical signals in the area for the scanning element to obtain color separation of the image so that the image can be displayed and formed; In an apparatus for converting into electrical signals a representation of a color image relating to a particular color, each of the signals being separated from the image by the color filter, comprising means for placing a replaceable color filter in front of the light-sensing element; each color filter is sized to be substantially smaller than the image plane and generally cover one or more scan lines, the fixed means being supported by a movable means, and the movable means being a continuum generated by the movement of the scanning element. Apparatus for converting a color image display into an electrical signal, characterized in that a color filter is moved with a scanning element in constant positional correspondence with a typical scanning line. (2) the fixing means for the color filters consist of a holder element, the holder element being arranged in a unit adapted to support the scanning element, and the holder element being arranged in the area of the unit and in positional correspondence with the scanning line of the scanning element; 2. Device according to claim 1, characterized in that it is arranged to apply a filter. (3) A device according to claim 2, characterized in that the fixing means for the color filters are arranged for fixing a single filter and for changing the means of the color filters. (4) The color filter fixing means is arranged to fix a plurality of color filters and to replace these color filters by sequentially moving the fixing means in relation to the scanning line of the scanning element. Apparatus according to claim 1. (5) The control means scans relatively during the scanning process in a predetermined pattern such that the color filter is moved and held in positional alignment with the scan lines made successively across the image plane during the scanning process. 5. The device according to claim 4, wherein the device and the color filter fixing means are movable along the movement path. (6) The control means holds the first color filter in positional registration with the scan line during a complete scan of the image for the formation of a first complete color separation signal, after which all intended color separation signals are Apparatus according to claim 5, characterized in that it holds the next color filter in positional alignment with the scan line during a complete scan of the image for the formation of the next color separation signal until formed. . (7) The control means holds the first color filter in positional registration with the scan line during scanning of one or a limited number of lines consisting of only a limited number of pixels, and thereafter controls all colors for the pixel. A second color filter is placed to keep the second color filter in positional alignment with the scan line for scanning the same pixels in the process until the separation signal is created, and then the process is such that all pixels in the image are separated. 7. Apparatus according to claim 5 or claim 6, characterized in that the second pixel is repeated until all desired colors have been scanned. (8) The scanning element consists of a column scanner, the column scanner being arranged to be moved laterally across the image plane by movable means, and the fixing means for the color filters comprising a number of apertures into which the color filters are inserted. The plate moves with the row scanner and maintains its position relative to the row scanner so that the various color filters supported by the plate can be varied and positioned directly in front of the row scanner. Device according to claim 5, characterized in that it is arranged to change. (9) The column scanner and the fixing means for the color filters each have movable means arranged to move the column scanner and the fixing means under the control of the control means in a manner adjusted and adapted to the scanning and color separation process. Apparatus according to claim 8, characterized in: (10) The fixing means for the row scanner and the color filters, in addition to common movable means, have an exchange device for changing the position of the color filters with respect to the row scanner. The device described in.