JPS6347893A - Bar code reader - Google Patents

Abstract

PURPOSE:To well perform the reading of the whole of a bar code, by selecting a signal by a signal selection control means, and reading the signal manually, when the array length of a bar exceeds the read possible range of a read sensor. CONSTITUTION:When the array length of the bar exceeds the read possible range of an image sensor 2, the movable contact (c) of a switch 5 is switched to a fixed contact (b) side, and a device main body is set so as to perform the manual scanning of the bar code. In such a case, a count up signal Sn is outputted when an N-ary counter 4 counts N-number of clock pulses Pc, and is supplied to a sample/hold circuit 6, and an electric signal Sd outputted from the image sensor 2 is sampled and held, and outputted when the array order of a photoelectric transducer is positioned at an N-th order. In such a way, the image sensor 2 is attached the same function as the read sensor in a manual scanning type bar code reader, and by obtaining the electric signal Sd in order, it is possible to read the whole of the bar code.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a barcode reading device equipped with a reading sensor formed by arranging a large number of photoelectric conversion elements.

(Prior Art) Conventionally, barcode reading devices are broadly classified into manual scanning type and automatic scanning type. A manual scanning type barcode reading device, as typified by a so-called light pen, uses a photoelectric conversion element such as a phototransistor as a reading sensor, and manually scans the barcode in the direction in which the bars are arranged. The barcode is read based on electrical signals sequentially output from the photoelectric conversion elements. On the other hand, an automatic scanning type barcode reading device uses a reading sensor, such as a CCD image sensor, in which a large number of photoelectric conversion elements are arranged, and aligns the reading sensor with the direction in which the bars of the barcode are arranged. The photoelectric conversion elements are arranged so that there is no relative movement, and an electric signal is output according to the arrangement order of each photoelectric conversion element, and a bar code portion is captured based on the electric signal. Although automatic scanning type barcode reading devices have the advantage of not requiring manual scanning, if the length of the barcode array exceeds the readable range of the reading sensor, parts of the barcode that are outside the readable range may be There was a problem that it could not be read.

Recently, in order to solve the above-mentioned problem in automatic scanning barcode reading devices, Japanese Patent Laid-Open No. 57-20
There is one shown in Japanese Patent No. 4977. When reading a barcode in which the length of the bar array exceeds the readable range of the reading sensor, the barcode reading device is moved so that the reading sensor is relative to the readable range on the left side of the barcode. It is placed so that it does not move, and the barcodes within that range are read and the data is stored.

Next, this barcode reading device is placed so that the reading sensor does not move relative to the readable range on the right side of the barcode, reads that range and stores this data, and the first stored data and the next stored data are stored. Compare the data and synthesize the data consecutively at the overlapped parts,
This allows one barcode to be read.

(Problem to be Solved by the Invention) However, in the case of the above-mentioned barcode, if the same pattern is continuous as shown in FIG. ffi? j
There is a problem in that the pattern in the f part cannot be distinguished from the patterns in each stored data, resulting in a situation where the data cannot be read. Such a problem also occurs when a barcode has multiple identical patterns.

The present invention has been made in view of the above circumstances, and its "
Firstly, when reading a barcode whose bar array length is within the readable range of the reading sensor, the device can be read by automatic scanning rather than manual scanning, and furthermore, the bar array length in the barcode is within the readable range of the reading sensor. To provide a barcode reading device that can read a barcode satisfactorily even when the pattern exceeds the readable range of a reading sensor or when the same pattern is continuous or exists in plurality. .

[Structure of the Invention] (Means for Solving the Problems) The present invention provides a reading sensor including a plurality of photoelectric conversion elements arranged to convert a barcode into an electrical signal, and an electrical signal output from the reading sensor. A case where the electrical signal is transferred to the signal processing circuit side in accordance with the arrangement order of the photoelectric conversion elements, and a case where only the electric signal corresponding to a predetermined one of the photoelectric conversion elements is transferred to the signal processing circuit side are selected. and signal selection control means.

(Function) When the length of the array of bars in the barcode is within the readable range of the reading sensor, automatic scanning is possible, so the signal selection control means selects the electrical signals output from the reading sensor as described above. Transfer to the signal processing circuit is selected in the order in which the photoelectric conversion elements are arranged.

If the array length of the bars in the barcode exceeds the readable range of the reading sensor, the signal selection control means processes only the electrical signal corresponding to a predetermined one of the photoelectric conversion elements. Select to transfer to the circuit. In this case, since the reading sensor essentially functions as one of the photoelectric conversion elements, the reading sensor has the same function as the reading sensor in a manual reading device.

Therefore, if you manually scan #4 against the barcode,
It is possible to read the entire barcode, and in this case, even if the barcode has consecutive or multiple identical patterns, the patterns are read sequentially by scanning. Barcodes can be read well.

(Example) An example of the present invention will be described below with reference to FIG. FIG. 1 shows an electronic control circuit in the main body of the apparatus (not shown). 1 is a clock pulse generation circuit, 2
is a reading sensor, for example, a CCD image sensor, which is constructed by arranging a large number, for example, M photoelectric conversion elements in one direction,
3 is an M-ary counter, 4 is an N-ary counter, 5 is a changeover switch, and 6 is a sampling & hold circuit. Then,
These N-ary counters4. The changeover switch 5 and the sampling & hold circuit 6 constitute a signal selection means 7. The clock pulse generation circuit 1 generates a clock pulse Pc.
is output and applied to the input terminal It of the image sensor 2, the clock terminal CLK of the M-ary counter 3, the clock terminal CLK of the N-ary counter, and one fixed contact a of the changeover switch 5. When the M-ary counter 3 counts M clock pulses applied to its clock terminal CLK, it outputs a count-up signal Sm from its output terminal O, and also clears the count value. The above count-up signal Sm
is applied to the input terminal I2 of the image sensor 2 and the clear terminal CLR of the N-ary counter 4. or,
The image sensor 2 has an M-ary counter 3 at its input terminal I2.
When the count-up signal Sm from the photoelectric conversion element is applied, the signal charge accumulated by the incident light on each photoelectric conversion element is transferred to the internal transfer section. Then, for each clock pulse Pc applied to the input terminal 11, the signal charges are shifted one element at a time in the internal transfer section and outputted from the output terminal O as an electric signal Sd. Therefore, this image sensor 2 outputs electrical signals Sd in order according to the arrangement order of each photoelectric conversion element. When the count-up signal Sm from the M-ary counter 3 is applied to its clear terminal CLR, the N-ary counter 4 is cleared and counts the clock pulse Pc. When the count value reaches N, the count-up signal is output from the output terminal O. Sn is output and applied to the other fixed contact of the changeover switch 5.

In this case, the count up value N of this N-ary counter is set to N
-M/2.

The changeover switch 5 is configured to apply the clock pulse Pc or count-up signal Sn to its output contact 5S by switching the movable electrode C. given to the analog switch. This sampling and hold circuit 6 is connected to the image sensor 2.
The electrical signal Sd applied from the internal analog switch is sampled and held in accordance with a signal (clock pulse Pc or count-up signal Sn) applied to the internal analog switch, and outputted, and applied to a signal processing circuit (not shown).

The operation of the above configuration will be explained. First, when the array length of the bars in the barcode is within the readable range of the image sensor 2, the changeover switch 5 is switched to one L so that the movable contact C is electrically connected to one fixed contact a side. , the main body of the apparatus is arranged so that the image sensor 2 does not move relative to the barcode. On the other hand, by the above-mentioned switching of the changeover switch 5, a clock pulse Pc is applied to the internal analog switch of the sampling and hold circuit 6,
The image sensor 2 samples and holds an electrical signal Sd outputted from its output terminal O in accordance with the arrangement order of each photoelectric conversion cable every time the clock pulse Pc is input, and outputs the sampled signal Sd. Thus, the electrical signal Sd- (in this case sampled and held) is transferred to the signal processing circuit in the order in which each photoelectric conversion element is arranged. Therefore, in this case, automatic scanning will be performed.

Next, if the length of the array of bars in the barcode exceeds the readable range of the image sensor 2, selector switch 5
After switching the movable contact C so that it is electrically connected to the other fixed contact, the main body of the device is manually scanned against the barcode. In this case, by switching the changeover switch 5, a count-up signal Sn is output when the N-ary counter 4 counts eight clock pulses Pc, and the count-up signal Sn is outputted to the sampling and hold circuit 6 via the changeover switch 5.
Therefore, the electrical signal Sd outputted from the image sensor 2 according to the arrangement order of the photoelectric conversion element is sampled and held by the sampling and hold circuit 6 and output when the arrangement order of the photoelectric conversion element is Nth. Therefore, the electrical signal Sd'' corresponding to the Nth photoelectric conversion element in the image sensor 2 (also sampled and held in this case) is transferred to the signal processing circuit side.In other words, the image sensor 2 has the same function as a reading sensor in a manual scanning type barcode reading device.

Therefore, by manually scanning the electrical signal Sd from the Nth photoelectric conversion element and sequentially moving it forward, the barcode can be read in its entirety. Moreover, in this case,
Even if the barcode has consecutive or multiple identical patterns, the barcode can be read satisfactorily because the patterns are sequentially read by scanning.

In the above embodiment, the sampling and Hall 1 circuit 6 is exemplified as the negative part of the signal selection control means 7, but a gate circuit called ill may be used instead of the sampling and Hall 1 circuit 6. In that case, the sampling and Hall 1 circuit 6 The Hall 1 circuit 6 may be provided on the signal processing circuit side.

The invention to be espoused is not limited to the above-mentioned embodiments, and can be implemented with various changes without departing from the spirit of the invention.

[Effects of the Invention] As is clear from the above description, when the length of the array of bars in a barcode is within the readable range of the reading sensor, the present invention automatically scans the barcode without manual scanning. It can be read, and it also works well when the array length of the bars in the barcode exceeds the readable range of the reading sensor, and in this case, when the barcode has consecutive or multiple identical patterns. It has the excellent effect of being readable.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a diagram showing an example of a bar code. In the figure, 2 is an image sensor (reading sensor), 3 is an M-ary counter, 4 is an N-ary counter, 5 is a changeover switch, 6 is a sampling and Hall 1 circuit, and 7 is a signal selection control means.

Claims (1)

[Claims] 1. A reading sensor consisting of a large number of photoelectric conversion elements arranged to convert barcodes into electrical signals, and transferring the electrical signals output from this reading sensor to the signal processing circuit side in the order in which the photoelectric conversion elements are arranged. and signal selection control means for selecting a case where only an electric signal corresponding to a predetermined one of the photoelectric conversion elements is transferred to the signal processing circuit.