JPS6139678A - Picture reading device - Google Patents

Abstract

PURPOSE:To obtain a low-priced reading device which can read both a transparent original and a printed original by reading the projection image for the transparent original of a film, etc., and reading it with a reflection light for the printed original of color. CONSTITUTION:An original stand 41 is made of a material which transmits light, a printed original is placed on the stand, illuminated with a light source 51 and a reflection light is read by a sensor 48. On the other hand, when a transparent film 45 is read, light, which is transmitted by an illumination light from a light source 43, is expanded by a projection lens 46, reflected by a reflection mirror 42 and expanded and projected on the original stand 41. An air image projected on the original stand 41 further transmits the original stand 41, and is image-formed to the sensor 48 by an image-formation lens 47. Like this, the printed original can be read by the reflection light and the film original can be read by a transmission light, and further, since the size of the original stand is not limited, a low-priced reading device can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to an image reading device, and in particular, RlG, B
The color image information input to the sensor via the color filter is A/D converted as a signal, and is sent to the buffer memory,
The present invention relates to an image reading device for a recording device that records images on a printer via a color converter and a pattern generator.

[Prior art]

2. Description of the Related Art Conventionally known apparatuses for reading color originals include those using a color scanner used in general printing plate making, and a method of photographing using a color camera. FIG. 1 shows an example of a recording apparatus equipped with a color image reading device using such a color scanner.

Note that the right half shows the reading device, and the left half shows the recording device. In this example, both opaque originals such as general printed matter and transparent originals such as silver halide film are This is an example of a device that can read .

That is, 1 is a document cylinder made of a transparent material, 2 is a light source that sends light to the cylinder 1, and the cylinder 1 is rotated by a drive motor 4 together with a recording cylinder 3.
5 is a threaded rod provided parallel to the axes of cylinders 1 and 3, 6 is a scanning head screwed onto the threaded rod 5, and 7 is a head 6.
8 is a color computer that performs processing based on information regarding the color of the image obtained from the scanning head 6.

The relationship between the original cylinder 1, the light source 2, and the scanning head 6 is configured as shown in FIG. 2, and the light emitted from the light source 2 is reflected by the total reflection mirror 10, The upper transparent original, for example, a color negative or positive film, is transmitted through it and captured by the pickup lens 11 of the head 2, and further reflected by the second total reflection mirror 12, and then transferred to the photolysis device 13. Filter 14
It is separated into three colors via R914B and 14G.

In this way, the decomposed lights are converted into electric currents by stimulating multiplier tubes (not shown), and sent to the color computer 8 shown in FIG. An image is recorded on the recording cylinder 3 at 15. 16 is a scanning motor for the output head 15. In the case of a reflective original, the light source is switched from the light source 2 shown in FIG. The reflected light reflected from the original document is captured by the pickup lens 11, and the image is read by the same operation.

Furthermore, FIG. 3 shows a lens system 7 for photographing with a color camera, where an imaging lens using a 31-bright zoom lens is used, and the light flux from an object (not shown), that is, a document, is combined with the imaging lens 31 and three colors. Decomposition system prism 32R
, 32B and 32G, and are separated into three colors and converted into electric current by each image pickup tube.
The image is then input to a color computer via a gam/D converter and subjected to image processing.

However, since all of these image reading devices are configured to separate the light beam into three colors on the same optical path, the amount of light for each color is small, and therefore the reading speed is affected by the response of the sensor. In addition, it is not easy to optically match the imaging positions of the individual color-specific optical images obtained by the sensor, and the apparatus becomes expensive.

Furthermore, in the color scanner apparatus shown in FIGS. 1 and 2, the size of the document to be read is limited by the size of the document cylinder 1.

In addition, in order to solve these problems, we have also
There is an image reading device disclosed in No. 4857, but this device cannot use transmitted light for transparent originals such as negative color or positive color film, and furthermore, the original is fed by rollers. As in the example of FIG. 1, the size of the document is limited.

〔the purpose〕

The purpose of the present invention is to solve these problems by making it possible to read images of drawings, color printed originals, etc. using reflected light, and for transparent originals such as film, using transmitted light.
Furthermore, it is an object of the present invention to provide an image reading device which has no limitations on the size of a document table, etc., and can be obtained at a lower cost than the color scanner type device using a cylinder as described above.

〔Example〕

Embodiments of the present invention will be described in detail below based on the drawings.

4 and 5 show the principle of the image reading apparatus of the present invention. FIG. 4 shows an image when reading an image from a transparent original such as a color film, and FIG. 5 shows an image from an opaque original such as a printed matter. Shows the status when reading .

In FIG. 4, numeral 41 is a document table that transmits light; 42 is a reflective mirror plate that can be rotated around a hinge 42A;
In the state shown in the figure, the reflecting mirror plate 42 is maintained at an angle of, for example, 45 degrees with respect to the document table 41. 43 is a light source for projection; 44 is an aspherical reflecting mirror provided on the back side of the light source 43; The irradiated light beam passes through the film 45, is further magnified by the projection lens 46, is reflected by the reflector plate 42, and is projected as an enlarged image onto the document table 41.

That is, in this case, the aspherical reflecting mirror 44 and the projection lens 4
6 and the film 45 are arranged so that an image with even light intensity can be formed on the document table 41.
The aerial image projected onto the document table 41 can be further transmitted through the document table 41 and formed into an image on the imaging lens 471 and the sensor 48. The sensor 4B will be explained in detail later, so it is not shown here. However, each line sensor consists of three sets of line sensors arranged in parallel. An image can be separated into three colors: red (R), green (G), and blue (B).

Therefore, the image from the film 45 that is formed on the sensor 48 via the imaging lens 47 is separated into the three colors of R2G and B, converted to the corresponding voltages, and then amplified and multicolored. In this figure, 51 and 52 arranged on the same side as the sensor 48 and the imaging lens 47 of the document table 41 are a reflecting light source and an aspherical reflecting mirror, respectively. However, these light source 51 and reflective mirror 52 are used when reading an original by reflection, which will be described later, and therefore are not used in the state shown in FIG. 4.

Next, referring to FIG. 5, a case will be described in which the apparatus of the present invention reads an image from a reflective original such as a color print or a color print photograph corner. In this case, by the switching operation, the reflecting mirror plate 42 is folded from the state shown in FIG. 4 to the state parallel to the document table 41 as shown in FIG. ．． light source 4
3 and the aspherical reflecting mirror 44 are both pulled down below the document table 41, and become unused.

That is, in this example, the reflecting mirror plate 42 is used as a document suppressing plate, and the document 50 for reflection is held between the document table 41 and the document pressing plate 42 . In this way, the light source 51 is turned on instead of the light source 43, the document 50 is irradiated by the reflecting mirror 52 without causing unevenness in the amount of light, and the reflected light is imaged on the sensor 48 via the imaging lens 47. Ru. In addition,
The reading process after color separation by the sensor 48 is the same as that described above, so the explanation will be omitted.

FIG. 6 shows an example of a mechanism for main scanning and sub-scanning of a carriage 53 loaded with a reflecting light source 51, its reflecting mirror 52, an imaging lens 47, and a sensor 48 in the document reading apparatus of the present invention. With such a mechanism, it is possible to read an image using reflected light from an opaque original as described with reference to FIG.

In FIG. 6, 54 is a threaded rod that causes the carriage 53 to scan in the main scanning direction of arrow X, 55 is a guide shaft that guides the carriage 53 in the main scanning direction, 56 is directly connected to the threaded rod 54, This is a drive motor that moves the carriage 53 by rotating a threaded rod 54.

A threaded rod 54 and a guide shaft 55 on which the carriage 53 is reciprocally supported are supported by a holding member 57. Furthermore, 5
8 is a threaded rod for moving this holding member 57 in the sub-scanning direction indicated by arrow Y, that is, a direction perpendicular to the main scanning direction X, and 59 is its guide shaft. Therefore, these threaded rods 58 and guide shafts 59 are connected to the shaft support 60A of the housing 60.
and 60B. Reference numeral 61 denotes a pulse motor or a servo motor for moving the holding member 57 in the sub-scanning direction by rotating the threaded rod 58.

Furthermore, 70 is a circuit case loaded on the carriage 53, and the circuit case 70 houses an output amplifier and an A/D converter for the sensor 48 (not shown). Although the document suppression plate 42 is not shown in this example, when the opaque document 50 is placed on the document table 41 and the image is read, the document suppression plate 4 (not shown) is placed on the document table 41.
2 is folded to hold the original.

Next, the multiple reading operations performed by the sensor 48 when reading an image by such a document reading device will be explained with reference to FIG. A) Red, green, and blue color filters 48R, 48G, and 48B are provided on the pixel elements 48S arranged in three rows.

Therefore, a color original 50 (not shown) is now placed on the original table 41.
is placed, the light beam from the light source 51 is irradiated onto the effective reading range 50A of the original 50 on the original platen 41 by the reflecting mirror 52 so that there is no uneven irradiation, and thus,
The image in this range of 50 mm is then further inverted left and right and forward by an imaging lens 47 and formed on a sensor 48 .

That is, the image in column A1 in the reading range 50A is
Filter 48R, A2 column image filter 48G,
Furthermore, the images of the 53 columns are inputted to the pixel elements 488 arranged below through the filter 48B, and voltages corresponding to red, green, and blue are output from each pixel element column.

Here, as shown in FIG. 6, when the carriage 53 loaded with the sensor 48 and the like is performed in the main scanning direction, assuming that the X direction is the main scanning direction and the Y direction is the sub scanning direction,
Image rows A1, A2, and A2 in the reading range 50A
If the distances P1 and P2 between P1 and A3 are not equal, these three colors will not be detected at the same location, so it goes without saying that such consideration must be taken when configuring the sensor 48.

Next, the control circuit of the image reading apparatus of the present invention will be explained with reference to FIG. Here, 71 is a signal processing circuit including an amplifier, an A/D converter, and a sensor driver, and as mentioned above, the red, green, and blue analog signals R, G, and B output from the sensor 48 are signal processed. The signal is amplified and A/D-converted by a circuit 71, and then sent to a shading correction circuit 72, where the color shading is corrected and sent to a computer 73.

The computer 73 has a memory section, a sequence control section, and an image processing section. The color signal is controlled to be output from the sensor 48 via the sensor driver in accordance with the timing, and the operation of moving the holding member 57 in the sub-scanning direction after reading in the main-scanning direction is repeated.

Note that the sensor 48 is connected to the computer 7 via the above-mentioned path.
The signal input to 3 is temporarily stored in the memory section,
Furthermore, a series of adjustment processes such as color correction, gradation, edge enhancement, and dither processing are performed in the image processing unit, resulting in cyan (0).
j Magenta (B), Yellow (1) and Black (B
K) is separated into color signals and output to the printer 75.

The above has described the case of reading from an opaque original, but in the case of a transparent original, the projected image from the transparent original is formed on the original platen 41 as in the example shown in FIG. The formed image is scanned by performing main scanning and sub-scanning similar to those described above, and a detailed explanation thereof will be omitted.In addition, in this example, the document table 41 is fixed. , the carriage 53 loaded with the sensor 48 was moved, but the carriage 53 was moved instead.
may be fixed and the document table 41 may be moved. In this case, the optical system that images the film 45 onto the document table is also moved with the document table.

In addition, in this example, since reading is performed using a sensor with a relatively short length, the carriage must be moved in the main and sub-scanning directions, but a sensor with a number of reading pixels that does not reduce resolution is used. If the width direction of the document is covered, the carriage or the document table only needs to be moved in one direction.

Furthermore, it is of course possible to read monochrome images other than color images.

〔effect〕

As described above, according to the present invention, light is projected onto a fixed document table that allows light to pass therethrough and a transparent document set at a position away from the document table, and an image obtained by the transmitted light is reflected. A device that reflects light from a plate and forms an image on the document table, and a reflected image obtained by irradiating the document placed on the document table or an image of the transparent document imaged on the document table. a device for forming an image on a sensor, a sensor having pixel elements arranged in parallel so that three color signals of red, green, and blue can be generated for discrimination; A carriage that holds and scans a device for forming an image together with a sensor, and controls the carriage to scan in a direction perpendicular to the pixel elements arranged in parallel in relation to the color signal generating pixel array of the sensor. When reading from a transparent original, the image on the original platen obtained by projecting light onto the transparent original is re-imaged on the sensor, and the image reading is performed by scanning the carriage. However, in the case of opaque originals, the reflected image from the original placed on the original platen was formed on the sensor, and the carriage was scanned using the image to read the image. The color at the point can be read in red, green and blue tones by a scanning mechanism operating in relation to the sensor position, making it extremely suitable as an input device for ultra-high precision image recording devices.
Furthermore, by using the above-mentioned reflector as the document suppressing plate on the fixed document table, it can be folded and the entire device can be made compact.

[Brief explanation of drawings]

Figure 1 is a perspective view showing the outline of the configuration of a conventional color scanner type image reading device, Figure 2 is a schematic diagram showing the configuration of its main parts, and Figure 3 is the optical system of a conventional color camera. FIGS. 4 and 5 are diagrams showing the basic structure of the image reading device of the present invention in two modes: when reading from a transparent original and when reading from an opaque original; FIG. 7 is a perspective view showing an example of the configuration of the image reading device of the present invention, FIG. 7 is a schematic perspective view for explaining the configuration of the color identification sensor and the multiple document reading operations performed by the sensor, and FIG. 8 is the perspective view of the present invention. FIG. 2 is a configuration diagram of a control circuit of an image reading device. (17),. DESCRIPTION OF SYMBOLS 1... Original cylinder, 2.20...-Light source, 3... Recording cylinder, 4.7... Drive motor, 5...-Threaded rod, 6... Scanning head h 8... Computer , 10.12... Total reflection mirror, 11... Pickup prism, 13... Photolysis device, 14R, 14B, 14G... Filter, 15...
・Output head, 16...Motor, 31...Imaging lens, 32R, 32B, 32G...Prism, 41...
- Document table, 42 - Reflector plate, 42A - Hinge, 43.51 - Light source, 44.52 - Aspherical reflector rod 45 - Film, 46 - Lens 1 47 - ...Imaging lens, 48...Sensor, 48S...Pixel element, 48R, 48G, 48B...Filter, 50...
- Original, 50A... Reading range, 53... Carriage, 54... Threaded rod, 55.59... Guide shaft, 56.61... Drive motor, 57... Holding member, 58 ... Threaded rod, 60... Housing, 70... Circuit case, 71... Signal processing circuit, 72... Shading correction circuit, 73... Computer, 74... Driver, 75... ...Printer. +4R

Claims (1)

[Claims] 1) A document table that can transmit light, an optical system that forms a transparent image of the transparent document on the document table, and is arranged in parallel and is capable of generating color signals in the form of a line. a sensor having a pixel array;
a second optical system that images a reflected image obtained by irradiating a document placed on the document table or a transmitted image formed on the document table by the optical system on the sensor;
means for moving the document table and the second optical system relative to the pixel array in a direction perpendicular to the pixel array in accordance with an interval between the pixel arrays; An image reading device characterized by: 2) The image reading device according to claim 1, further comprising a reflective plate on the document table that guides the transparent image of the transparent document, and the document is placed on the document table and the reflected image is reflected. An image reading apparatus characterized in that the original is pressed by the reflective plate when obtaining the original.