JPH0324708B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for reading two-dimensional data such as letters, numbers, marks, etc. using a reader incorporating a one-dimensional image sensor.

For example, as shown in FIG. 1, by moving a hand scanner 3, which is a reader configured to be operated by hand, over a document 2 on which data 1 such as letters, numbers, marks, etc. are drawn, the data is read. There is a reading device. In this case, the hand scanner 3 has a built-in one-dimensional image sensor, and can read XY two-dimensional data by moving over the document 2 in a direction X orthogonal to the scanning direction Y of the sensor's output. At this time, since the hand scanner 3 is manually operated, its moving speed is not necessarily constant, but rather varies greatly. Therefore, as shown in FIG. 2, the hand scanner 3 includes a one-dimensional image sensor 4 such as a CCD.
Additionally, a movement pulse generator 5 is provided which outputs a movement pulse _P1 every time the scanner 3 is moved a certain distance in the X direction. Then, based on this movement pulse _P1 , the read data processing circuit 6 output from the hand scanner 3 samples. Thereby, the data processing circuit 6 can sample the read data D ₀ at every fixed moving distance regardless of fluctuations in the moving speed of the hand scanner 3. Therefore, a constant dimensional relationship is always maintained between the data 1 on the document 2 and the sampled read image. Here, in the conventional data reading device, the moving pulse _P1 is passed through a frequency divider 7 to appropriately divide the frequency, and the obtained pulse _P2 is given to the data processing circuit 6 as a sampling timing signal. be. If the frequency division ratio of the frequency divider 7 is set to 1/2, for example, one sampling pulse _P2 will be emitted for every two moving pulses _P1 . Therefore, for example, if the movement pulse _P2 is emitted every time the hand scanner 3 moves by 0.2 mm, then the read data _D0 is sampled every time the hand scanner 3 moves by 0.4 mm. That is,
Data 1 on manuscript 2 has a sampling interval of 2
By expanding to twice the size, the image can be read while being reduced to 1/2 in the moving direction X of the hand scanner 3. Similarly, if the frequency division ratio of the frequency divider 7 is set to 1/3, reading can be performed with a reduction ratio of 1/3 compared to normal reading. Also, if the period of the movement pulse P ₁ is set to 1/2 of the length in advance,
When the frequency division ratio is 1, that is, when no frequency division is performed, a double magnification can be obtained.

However, when setting the sampling interval as described above, the reduction rate or enlargement rate can only be obtained at random specific values such as 1/2, 1/3, etc. For example, if the reduction rate is set to 0.7 times. thing,
With the conventional data reading device described above, it is not possible to freely set the reduction ratio to a value that is not divisible by a simple integer, or to continuously vary the reduction ratio and enlargement ratio.

This invention has been made in view of the above-mentioned conventional problems, and its purpose is to provide a system with a relatively simple configuration that does not limit the sampling interval of read data to a specific integer relationship. Provided is a data reading device that can be set arbitrarily and variably, thereby allowing the reduction or enlargement ratio of a read image to be freely and continuously variably set even to odd values with simple configuration and operation. It's about doing.

Hereinafter, embodiments of the present invention will be described in detail based on the drawings. Note that the same reference numerals are used for parts common or corresponding to those of the conventional art.

FIG. 3 shows an embodiment of a data reading device according to the present invention. The apparatus shown in the figure is first moved over a document 2 in a direction X orthogonal to the scanning direction Y of the built-in one-dimensional image sensor 4, as in the conventional example described above, to obtain two-dimensional data 1 in X and Y. It has a manually operated reader or hand scanner 3 for reading. The hand scanner 3 also includes a movement pulse generator 4 that outputs a movement pulse _P1 every time the hand scanner 3 is moved a certain distance in the X direction. Additionally, this moving pulse
A data processing circuit 6 is provided that samples read data D ₀ output from the hand scanner 3 based on P ₁ .

This embodiment further includes a period detection circuit 8 that generates an analog signal having an analog value V ₁ corresponding to the period T ₁ of the moving pulse P ₁ and a reciprocal of the analog output value V ₁ of this detection circuit 8. Analog amount corresponding to the moving speed of a certain image sensor 4
A speed detection circuit 9 that calculates V ₂ and an analog quantity V ₂
An integration circuit 10 that calculates an analog quantity V ₃ corresponding to the position of the image sensor 4, that is, a moving distance from the initial time by integrating the above, and an analog quantity k ₃ E corresponding to a fixed distance of the moving distance of the image sensor 4 are set. and a variable frequency oscillation circuit that generates a pulse every time the analog quantity V ₃ exceeds an integral multiple of the analog quantity k ₃ E, that is, every time the moving distance of the image sensor 4 exceeds an integral multiple of the above-mentioned fixed distance. A circuit 12 is provided. Here, as the period detection circuit 8, for example, a capacitor C is charged via a resistor R, and the peak value of the sawtooth wave obtained by discharging the capacitor C every time a moving pulse P ₁ is input is set to a period T ₁ . Corresponding analog quantity V ₁
A circuit that generates can be used. Furthermore, in this embodiment, an AD converter is used as the oscillation circuit 12, and the converted input of this AD converter is
By inputting V ₃ as a reference input and k ₃ E, the least significant bit of the AD converter outputs a pulse every time V ₃ becomes an even multiple of k ₃ E. This oscillation circuit 1
By supplying the output of No. 2 to the data processing circuit 6 as a sampling timing signal, the analog adjustment circuit 11 is configured to continuously change the reading sampling interval of data 1. That is, the analog adjustment circuit 1
Since the analog quantity k ₃ E of 1 can be arbitrarily and variably set, the sampling interval of the read data D ₀ can be freely and continuously variably set.
Furthermore, the reduction ratio or enlargement ratio of the sampled read image can be continuously variably set with only a simple adjustment operation.

Hereinafter, the above-described embodiments of the present invention will be explained in more detail using mathematical formulas.

The period detection circuit 8 generates an analog quantity V ₁ proportional to the period T ₁ of the movement pulse P ₁ , and the speed detection circuit 9 generates an image corresponding to one of the movement pulses generated by the movement pulse generator 5. For the moving distance d of the sensor 4 and the analog quantity V ₁ above,
Analog quantity V ₂ proportional to d/v ₁ or d/T ₁
Output. Therefore, the analog quantity V ₂ has the relationship of V ₂ =k ₁ ·d/T ₁ =k ₁ a (1) where a is the moving speed of the image sensor 4 and k ₁ is a constant of proportionality.

The analog output _V3 of the integrating circuit 10 has a proportionality constant
As k ₂ , V ₃ = k ₂ ∫ ₀ ^t V ₂ dt = k ₁ k ₂ ∫ ₀ ^t adt = k ₁ k ₂ x(t) (2) Then, the moving distance from time t = 0 x(t) is proportional to.

Here, when inputting the analog quantity k ₃ E=k ₁ k ₂ d'/2 (3) as the reference input of the AD conversion circuit 12, the AD conversion circuit 12
One least significant bit signal _P2 is generated every time an integer multiple of the moving distance d' passes.

On the other hand, the reduction ratio K of the image sensor in this case is given by K=d/d' (4), so from equations (3) and (4), k ₃ E=k ₁ k ₂ /2・d/K, i.e. K=k ₁ k ₂ /2k ₃ ·E (5), and by adjusting the parameter k ₃ of the analog adjuster 11, the reduction rate can be changed continuously. Furthermore, it can be seen from equation (5) that similar results can be obtained by changing k ₁ or k ₂ .

Here are some of the other examples:
The moving pulse generator 5 generally has a configuration in which a pulse encoder is connected to a roller that rotates in contact with the document 2 being moved by the hand scanner 3. A sensor for reading this mark may be provided on the side of the hand scanner 3, and a detection pulse for each mark may be output as the movement pulse while the hand scanner 3 is moved. Alternatively, a filter may be provided between the speed detection circuit 9 and the integration circuit 10, so that the sampling pulse _P2 can be generated every time the device moves approximately a certain distance even when the speed of movement changes rapidly. good.

As described above, in the data reading device according to the present invention, even with a relatively simple configuration and operation, the sampling interval of read data can be set arbitrarily and variably without being limited to a specific integer relationship. This allows the reduction or enlargement ratio of the read image to be freely and continuously variably set.

[Brief explanation of drawings]

FIG. 1 is a plan view showing a reader portion of a data reading device, FIG. 2 is a block circuit diagram showing an example of a conventional data reading device, and FIG. 3 is a block diagram showing an embodiment of a data reading device according to the present invention. It is a circuit diagram. 1... Data such as letters, numbers, marks, etc., 2...
Original, 3...Hand scanner (reader), 4...
One-dimensional image sensor, 5... Moving pulse generator, 6... Data processing circuit, 8... Period detection circuit, 9... Speed detection circuit, 10... Integrating circuit, 1
1... Analog adjustment circuit, 12... AD conversion circuit, D ₀ ... Read data, P ₁ ... Movement pulse, P ₂
...Sampling pulse, _V1 to _V3 ...Analog output voltage, k...Variable setting coefficient.

Claims (1)

[Claims] 1. A reader that reads data in two dimensions, X and Y, by moving over the document in a direction A moving pulse generator that outputs pulses, a data processing circuit that samples read data output from the reader based on the moving pulses, and a cycle that generates an analog signal having an analog amount corresponding to the cycle of the moving pulse. a detection circuit, a speed detection circuit that detects the moving speed of the image sensor based on an analog signal output from the period detection circuit, and a pulse having a period corresponding to the moving speed of the image sensor determined by the speed detection circuit. an oscillation circuit that generates a signal and supplies it as a sampling timing signal to the data processing circuit; and an adjustment circuit that continuously and variably adjusts the correspondence between the period of the pulse output from the oscillation circuit and the movement speed. A data reading device comprising: