JPS62185456A - Two-color picture reader - Google Patents

Abstract

PURPOSE:To simplify the adjustment and to reduce the space occupied by an optical system by applying color separation into two colors of red and black and applying photoelectric transducing to the colors and outputting the result. CONSTITUTION:The light from a fluorescent lamp 1 irradiates an original 2 uniformly and the reflected light from the original 2 is condensed by a lens 3. The condensed light is formed onto a CCD 6 through a disk filter 4 driven at a constant speed by a motor 5. The CCD 6 applies self-scanning in the main scanning direction and a picture signal is obtained by the photoelectric transducing. The disk filter 4 consists of the 1st color filter 8 transmitting the wavelength component of the red region, the 2nd color filter 9 transmitting the wavelength component other than the red color region and a light shield part 10. Further the disk filter 4 has a projection 11 as a means representing a turning position. The light is subjected to color separation by driving the disk filter 4 provided with the 1st color filter 8 transmitting the wavelength component of the red region, the 2nd color filter 9 transmitting the wavelength component other than the red region and the light shield part 10 provided at the boundary between the two kinds of color filters 8, 9 in this way. Then the CCD 6 applies photoelectric transducing.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a color image reading device that separates red and black into two colors, photoelectrically converts them, and outputs them.

2. Description of the Related Art Conventionally, this type of red and black two-color image reading device
The configuration was as shown in the figure. That is, the document 62 is sub-scanned in the direction of arrow e by a paper feed mechanism (not shown). The light from the fluorescent lamp 61 uniformly illuminates the original 62, and the reflected light from the original is focused by the lens B3. The focused light is divided into light containing wavelength components in the red region by a dichroic mirror 64 having wavelength characteristics as shown in FIG.
The light is separated into complementary color components. The separated lights are each sent to a CCD image sensor (hereinafter abbreviated as COD) 6.
5.66 for photoelectric conversion.

Problems to be Solved by the Invention However, since the above-mentioned conventional two-color image reading device uses two CCD image sensors,
High precision is required to align the bits of each CCD image sensor, and therefore adjustment is extremely difficult and requires advanced technology. Another disadvantage is that the optical system occupies a large space.

The present invention has been made in view of the above-mentioned conventional circumstances, and
Accordingly, an object of the present invention is to provide a novel two-color image reading device which makes it possible to eliminate the above-mentioned drawbacks inherent in the conventional technology.

Means for Resolving the Problems In order to achieve the above object, the two-color image reading device according to the present invention includes a first color filter that transmits wavelength components in the red region and a first color filter that transmits wavelength components other than the red region. A disc filter comprising a light shielding part at the boundary between a second color filter that transmits the light and a color filter of Oii Note 2 rffl, and a means for indicating a rotational position, and a sensor for detecting the rotational position of the disc filter. ,
11. Color-separated light beams using circular filters.
1 C to convert! ; It has a D image sensor and is constructed by rotating the disk filter at a constant rate.

Embodiments Next, preferred embodiments of the present invention will be specifically explained with reference to the drawings.

FIG. 1 is a schematic diagram showing an embodiment of the present invention. In FIG. 1, a document 2 is sub-scanned in the direction of arrow a by a paper feed mechanism (not shown). The light from the fluorescent lamp l uniformly illuminates the original 2, and the reflected light from the original 2 is focused by the lens 3.

The collected light passes through a disc filter 4 that is rotated at a constant rate by a motor 5, and is imaged on a CCD 6. The CCD 6 self-scans in the main scanning direction and obtains an image signal through photoelectric conversion. The rotation timing of the disc filter 4 is detected by a rotation position detection sensor 7.

FIG. 2 shows an example of the structure of the disc filter 4. The disc filter 4 includes a first color filter 8 that transmits wavelength components in the red region, a second color filter 9 that transmits wavelength components other than the red region, and a light shielding portion IO.

Further, the disc filter 4 is provided with a protrusion II as a means for indicating the rotational position.

FIG. 3 shows the wavelength characteristic I2 of the first color filter 8 and the wavelength characteristic +3 of the second color filter 9. As shown in the figure,
Each color filter separates light at a wavelength of approximately 600 nm.

Timing diagram (1) in FIG. 4 shows the shift clock of the CCD 6. At H level (section C) in the figure, all signal charges in the photosensitive section C (D) are transferred to the transfer section.

Ru.

Timing diagram (2) shows the timing when the disk filter 4 shown in FIG. 2 rotates in the direction of the arrow. Here, TI indicates one cycle of the disc filter 4. Further, Rn indicates the timing at which the light imaged on the CCD 8 passes through the first color filter 8, Rn indicates the timing at which the light passes through the second color filter 9, and the subscript n indicates the circle that rotates once. It represents the cycle of the plate filter 4. The section with symbol d corresponds to the section of the light shielding part IO shown in FIG. In this section of d, CC
Light to D6 is blocked. Furthermore, the section d is controlled to be longer than the section C in the timing diagram (1). 1 and 2 are the COD of the light that passed through each color filter.
6 shows the time accumulated in Kameari.Next, the light shielding part I
The reason for providing O will be explained. The T2 section is shown in the timing diagram (
If the CCD 6 crosses both sides of the section C in 1), it will no longer be possible to accurately read each color information, so it is necessary to precisely match the rotation timing of the disk filter 4 with the CCD shift clock in timing diagram (1). There is. but,
The above-mentioned adjustment is extremely difficult when considering rotational unevenness of the motor 5 and the like. The present invention provides a light shielding section at the boundary of each color filter in order to prevent mixing of separated optical information. Setting 0 solves the above problem.

Timing diagram (3) shows the output signal of the rotational position detection sensor 7 shown in FIG. 1 for timing the color filters.

FIG. 5 shows the output signal VR of the CCD 8 when the reflected light from the original 2 passes through the first color filter 8 and the output signal Vπ when it passes through the second color filter 9. The white information of the document is obtained when the signals VR and V' are both at high level, the black information is obtained when the signals VR and vK are both low level, and the red information is obtained when VR is high level and vK is low level.

In this way, a red and black two-color image reading device can be constructed.

In this embodiment, the color filters of the disk filter 4 are one that transmits wavelength components in the red region and one that transmits wavelength components other than the red region, with a combination of t and n of 1χ·t, which is 131 Pairwise combinations are also possible.

Further, although the disc filter 4 is mounted between the lens 3 and the cco e, it may also be mounted between the document 2 and the lens 3.

As described in detail, according to the present invention, a first color filter that transmits wavelength components in the red region, a second color filter that transmits wavelength components other than the red region, and the two types of colors are provided. Color separation of light is performed by rotating a disc filter equipped with a light shielding part provided at the border of the filter, and light is separated by COD.
By converting, it is possible to easily configure a two-color image reading device with an optical system that is easy to adjust and takes up a small space.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram showing one embodiment of the present invention, FIG. 2 is a structural diagram of a disc filter used in the embodiment of FIG. 1, and FIG.
The figure shows the wavelength characteristics of each color filter, and (1) in Figure 4 shows the CO
Timing diagram of the shift clock in D, (2) is a timing diagram when the disk filter rotates, (3) is a timing diagram of the rotational position detection sensor, Figure 5 is an explanatory diagram of color information detection, and Figure 6 is FIG. 7 is a schematic diagram of a conventional two-color image reading device, and FIG. 7 is a wavelength characteristic diagram of the dichroic mirror used in FIG. ■01. Fluorescent light, 201. Manuscript, 3. ,, L-ns, 4
000 disc filter 0. Motor, 6, , ,
CCD image sensor, 7. ,,rotational position detection sensor,
8. , , a color filter that transmits wavelength components in the red region; 9.
,,7 outside the red area! ! ! Filter that transmits long components, 1G, , n tip, Il, , protrusion indicating rotational position

Claims (1)

[Claims] A first color filter that transmits wavelength components in the red region, a second color filter that transmits wavelength components other than the red region, a light shielding portion provided at the boundary between the two types of color filters, and means for indicating a rotational position. a disc filter comprising: a sensor for detecting the rotational position of the disc filter; and a CCD image sensor that photoelectrically converts light color-separated by the disc filter; A two-color image reading device characterized by constant rotation of a filter.