JP2794060B2 - Imaging device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Purpose of the Invention] (Industrial application field) The present invention relates to an image pickup apparatus used for an apparatus for printing out characters and figures drawn on, for example, a blackboard, a white board, or a wall of a bulletin board. .

(Prior art) Characters and figures drawn on various walls such as a blackboard are made incident through a lens, the angle of view is determined while monitoring with a viewfinder, and the image is scanned by a one-dimensional image sensor, and the result is obtained. A so-called image pickup printing apparatus has been proposed in which a printer is operated in response to an image signal received and characters and figures are printed out on paper.

In addition, an apparatus has been proposed in which a limiting member that limits an imaging range of the one-dimensional image sensor is provided, and only a specific portion such as a character or a figure can be imaged by adjusting the displacement of the limiting member.

As described above, when only a specific portion is imaged, it is desirable that the image to be printed out is an enlarged image. As a means for enlarging an image, it is conceivable to enlarge an image to be captured by a zoom lens or the like. However, an expensive zoom lens is required, which is disadvantageous in cost.

Therefore, it is conceivable to enlarge an image output by data processing.

When the image is enlarged by a general image processing method, the binarized data is held in a memory, and the data is increased by bit processing. For example, in order to exchange 3-bit data into 4-bit data, as shown in FIG. 4, a conversion table for multiplying data by 4/3 is provided.

(Problems to be Solved by the Invention) In the above-described method, a memory for holding data is required, and the magnification is also limited. Further, since the conversion pattern appears in the print output, there is a problem that the resolution is reduced.

The present invention has been made in view of the above problems, and can increase bit data without using a conversion table, and can also obtain an arbitrary magnification, and
It is an object of the present invention to provide an imaging device in which the output resolution does not decrease.

[Configuration of the invention]

(Means for Solving the Problems) An image pickup apparatus according to the present invention is an image pickup apparatus which converts an image pickup signal obtained by sub-scanning a one-dimensional image sensor by a motor into binary data and outputs the binary data. A limiting member for limiting the range, magnification setting means for setting a magnification in inverse proportion to a change in the imaging range in conjunction with the restriction member, and a clock signal for generating a clock signal having a frequency proportional to the magnification set by the magnification setting means A power source, a data holding unit having a plurality of stages of signal holding units for sequentially holding the binary data according to the clock signal, and a shift unit for shifting the motor in accordance with the set magnification.

(Operation) According to the present invention, when the imaging range of the one-dimensional image sensor is limited to 1 / N times by the limiting member, the magnification setting means sets, for example, the magnification inversely proportional to the change of the imaging range, for example, N times, and the clock signal becomes N times in proportion to this,
The binary data, which is the imaging result of the one-dimensional image sensor, is held in the data holding means every time an N-fold clock signal is generated, and the binarized data is held by being divided into N times. If the held data is output, an image signal enlarged by N times can be obtained. Further, in the sub-scanning direction, the motor is shifted according to the magnification, so that the sub-scanning speed becomes, for example, 1 / N times, and the scanning line is subdivided into N times. The same binary data as in the case of zooming is obtained.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

First, the overall configuration will be described with reference to FIG. In FIG. 2, a central processing unit (CPU) 46 has overall control. That is, the central processing unit 46 gives a lighting command to the columnar light sources 41 for detecting the imaging range when an imaging command is applied from the outside, and provides a drive pulse to the sub-scanning stepping motor 47 based on the imaging command. .

The stepping motor 47 moves a reticle (not shown) provided on the image plane and the one-dimensional image sensor 20 integrated with the reticle along the image plane. Further, the one-dimensional image sensor 20 is operated via the drive circuit 48 based on the imaging command. The output signal from each pixel of the one-dimensional image sensor 20 is subjected to waveform shaping by a waveform shaping circuit 49, and further subjected to binarization processing by a binarization circuit 50.

The central processing unit 46 outputs print data to the printer control circuit 51 on the basis of the binarized image pickup signal, and operates the printer 52. Then, the waveform shaping circuit 49
The output signal of each pixel whose waveform has been shaped is also applied to the comparator 53, where it is compared with the threshold value V _TH . This comparator 5
The output signal of No. 3 becomes a vertical (V) area signal which is one of the imaging ranges, and is added as an area determination signal to the area determination means which is a function performed by the central processing unit 46. Also,
An output signal of the sensor 43 for detecting the imaging range in the horizontal direction, that is, a horizontal (H) area signal is added to this area determination means as an area determination signal. Further, the central processing unit 46 is provided with a magnification setting means 11 for setting an output magnification to an arbitrary magnification.

The printer control circuit 51 has a shift register 12 and a clock signal source 13 as data holding means, as shown in FIG. The shift register 12 functions as a flip-flop 14 as a signal holding unit of a plurality of stages, for example, 1728 stages. The binary data, which is a serial signal generated from the central processing unit 46, is sequentially held each time a clock signal is input.

Also, each stage flip-flop of this shift register 12
The same number of latch circuits 15 are provided corresponding to 14, and these latch circuits 15 output 1728 clock signals from the clock signal source 13 and store the binarized data in each stage flip-flop 14 of the shift transistor 12. As a result, the data of the flip-flop 14 at each stage is input by a latch signal generated from the central processing unit 46 and held as dot signals for the 1728 dot line head.

Further, the clock signal source 13 generates a clock having a frequency proportional to the magnification set by the magnification setting means 11,
A programmable oscillator that changes the frequency of an output clock signal according to input data that is magnification data is used.

On the other hand, in the sub-scanning direction, the speed of the motor 47 is shifted by the transmission means 16 of the central processing unit 46 in accordance with the set magnification, for example, in inverse proportion to the set magnification.

 Next, the operation of the above embodiment will be described.

First, the user sets an imaging lens on a wall surface on which characters, figures, and the like to be printed out are drawn, and looks at an image captured on a viewfinder to control a V masking member or an H masking member for limiting an imaging range. By moving one or both of them, the range to be imaged from the image is set arbitrarily.

Next, when an imaging command is given, the central processing unit 46
First, the row-shaped light sources 41 are turned on, and the one-dimensional image sensor 20 at the starting position is irradiated. At the same time, the one-dimensional image sensor 20 is operated via the drive circuit 48 to generate an output signal for one line from each image. At this time,
A V masking member (not shown) is located between the row of light sources 41 and the one-dimensional image sensor 20, and the amount of light incident on the pixels in the masked portion is largely light, so that the output voltage is low. Level. Therefore, these output voltages are compared with the threshold value _VTH by the comparator 53 to obtain a V area signal as a result of the comparison. The area determining means of the central processing unit 46 determines an effective pixel which generates an output _{equal to} or _larger than the threshold value _{VTH based on the} V area signal, and detects a vertical (V) direction effective area.

In FIG. 3, A is the maximum imaging range, and B is the imaging range masked by the masking member.

The detection of the effective area in the horizontal direction is determined by the central processing unit 46 by the operation of the sensor 43, but the detailed description thereof is omitted here.

When the one-dimensional image sensor 20 horizontally moves along the coupling surface by the stepping motor 47, the image incident from the imaging lens is set, and the output signal a shown in FIG.
Is generated. The output signal a is shaped into a waveform and binarized as shown by a line b. The central processing unit 46 only outputs a portion corresponding to the effective area determined as described above, for example, only the data in the range B. Is output to the printer control circuit 51.

Here, since the portion of the range B is imaged, it is desirable to enlarge it to the size of the maximum imaging range A. Therefore, the magnification is set to A / B by the magnification setting means 11. Based on this magnification, the central processing unit 46 supplies magnification data, for example, 8-bit data, to the clock signal source 13 to multiply the frequency of the output clock signal by A / B. That is, 1728 clock signals are output during the transfer time of the binarized data within the range B shown in FIG. 3, and are sequentially held in the flip-flops 14 of the shift register 12. And 2 of 1 line
When the transfer of the digitized data is completed, that is, after the data is stored in each stage flip-flop 14 (1 to 1728) of the shift register 12, a latch signal is issued from the central processing unit 46, and the data of each stage is latched. 15 and is held as dot signals of the line head (1728 dots). Therefore, printing by this line head has a magnification of A / B times.

Further, the central processing unit 46 changes the speed of the motor 47 by the transmission means 16 according to the set magnification (A / B), and reduces the speed in the sub-scanning direction to B / A times. Even if the speed in the sub-scanning direction decreases in this manner, the paper feed in the printer 52 is kept constant, so that the sub-scanning direction of the obtained print data is expanded to A / B.

As the magnification setting means 11, a means that is linked with the imaging range limiting masking member and automatically sets the magnification in inverse proportion to the imaging range changed by the masking member may be used. Alternatively, each of the V and H area signals shown in FIG. 2 may be input and determined in the central processing unit 46 according to the ratio to the maximum value. At this time, if the magnification values of V and H are different, the smaller one is used as the system enlargement magnification by the central processing unit.
Set by 46.

Although a programmable oscillator is shown as the clock signal source 13, a voltage controlled oscillator may be used, but in this case, a D / A converter is also required.

〔The invention's effect〕

According to the imaging apparatus of the present invention, when the imaging range of the one-dimensional image sensor is limited by the control member, the magnification setting unit sets, for example, a magnification inversely proportional to a change in the imaging range, and sets an output magnification of binarized imaging data. Can be set to an arbitrary magnification, and the range of use can be expanded, for example, by changing the aspect ratio or enlarging the horizontally long one.

[Brief description of the drawings]

FIG. 1 is a main part showing an embodiment of an image pickup apparatus according to the present invention, FIG. 2 is a block diagram showing an entire structure, FIG. 3 is a characteristic diagram for explaining an image pickup range, and FIG. FIG. 9 is an explanatory diagram of bit processing using the conversion table of FIG. 11: magnification setting means, 12: shift register as data holding means, 13: clock signal source, 14: flip-flop as signal holding unit, 16: transmission means, 20 ...
One-dimensional image sensor, 47 ... motor.

──────────────────────────────────────────────────続 き Continuation of front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H04N 1/393

Claims (1)

(57) [Claims] 1. An imaging apparatus for converting an imaging signal obtained by sub-scanning a one-dimensional image sensor by a motor into binary data and outputting the binary data, wherein: a limiting member for limiting an imaging range for the one-dimensional image sensor; Magnification setting means for setting a magnification in inverse proportion to a change in the imaging range, a clock signal source for generating a clock signal having a frequency proportional to the magnification set by the magnification setting means, and a plurality of signal holding units. An image pickup apparatus comprising: a data holding unit that sequentially holds the binary data according to the clock signal; and a shift unit that shifts the motor in accordance with the set magnification.