SU1339602A2 - Line image reader - Google Patents

Abstract

The invention relates to computing and can be used, for example, in input devices in computers for alphanumeric and graphic information. The aim of the invention is to increase the reliability of reading. The device contains a block of 1 light filters, a block of 2 black photodetectors, a block of 3 photodetectors of the background level, information photodetector 4, stepper drive 5, drivers 6, 7 levels of background and black, analog subtractive element 8, voltage threshold generator 9 , comparator 11, standby multivibrator 12, counter 13 pulses, decoder 14, differentiating element 15 and key 16. Introduction of block 1 light filters with drive 5 and blocks 12-16. allows detecting colored spots and eliminating errors yvanii graphical elements. 3 il. i (L co 05 SO O HCHE

Description

The invention relates to computing, can be used, for example, in alpha-numeric and graphic information input devices in computers and is an improvement of the device according to the author. St. No. 1078A47.

The aim of the inventions is to increase the reliability of the information read.

FIG. 1 shows a functional diagram of the device; in fig. 2 shows the arrangement of photodetectors; in fig. 3 - time diagrams of signals.

The device contains a block of 1 light filters, a block of 2 black photodetectors, a block of 3 background level photodetectors, information photodetector 4 stepper drive 5, formers 6 and 7 background levels and black, analog subtractive element 8, voltage threshold generator 10

signals, the comparator 11, the waiting multivibrator 12, the counter of 13 pulses, the decoder 14, the differentiating element 15 and the key 16,

The device works as follows.

The luminous flux passing through the white (transparent) filter of the block 1 of replaceable light filters is supplied to the corrective photodetectors of the black and background levels, where it is converted into an elactric signal proportional to it, which enters the inputs of the formers 6 and 7 of the background and black levels, from which the signal enters the inputs of the analog subtractive element B, and its output signal through the driver 9 of the threshold voltage passes to the input of the comparator 11, which compares this signal with the signal from the output of block 10, as the spacing between the input level of the block 10 and the information signal, from the output of the comparator 11, a single pulse corresponding to the information spot under the information photoreceiver 4, starts the waiting multivibrator 12 and enters the counting input of the counter 13 pulses generated by the waiting multivibrator 12 generated by it impulse equal in duration to the time spent by the stepping motor iia

change all filters in the block of replaceable filters and return them to the initial state (light filter

white color), is fed to the start of the stepper motor 5, which changes the light filters in block 1.

On the falling edge of the pulse generated by the multivibrator 12, the differentiating element 15 and the key element 16 form a pulse readout of the pulse counter 13, which, arriving at its control input, transmits the recorded to

It has the number of pulses into the decoder, which, when this number corresponds to the number of filters in the block of replaceable filters plus one, outputs a single pulse corresponding to the presence of a black spot under the information photoreceiver, and zero otherwise indicates a color spot under the information photoreceiver 4. The dynamics of the device operation is explained by the voltage diagrams shown in FIG. 3: the subscript a shows the signal plot at the output of the information photodetector 4, under

, j photodetector is the background spot, as a result of which is compared with the signals at the output of black photoreceivers (plot b) and background (plot c), at the output of comparator 11 (plot g)

there is no start-up pulse of the waiting multivibrator 12, and the device proceeds to the analysis of the stroke information under the i, j photodetector. In this case, under it is a red spot, the signal at the output of the information photodetector 4 with a transparent (white) filter is less than or equal to the signal at the output of the black photodetector 2 (voltage diagram b),

as a result, a single impulse appears at the output of the comparator 11 (plot g), arriving at the counting input of the counter 13 pulses and at the start of the waiting multivibrator 12,

which generates a pulse (plot d), arriving at the input of the stepping motor 5, which changes when it is exposed to light filters in the block of replaceable light filters 1.

The colors of the light filters correspond to the spectral component of white and are designated by the letters: b - white (transparent), к - red, f - yellow, 3 - green, g - blue, with

blue, f - purple. At the output of the information photodetector 4, a pulse appears at the red filter (plot a), compared in amplitude with the pulse at the output of the photoreceiver background 3 (plot c), and the corresponding red spot under the information photoreceiver 4 As a result, the output of the comparator 11 (plot d) the pulse does not appear and the contents of the counter 13 does not increase by one. With the remaining light filters of the interchangeable .- optical filters 1 at the output of the information photoreceiver 4 (plot a), pulses appear that are smaller in amplitude of the pulses at the output of the photoreceiver 2 black (plot b), resulting in a comparator

11 (plot g), single pulses appear. On the falling edge of the pulse from the output of the waiting multivibrator

12 (plot d), the stepping motor b stops its operation and in the block of replaceable light filters 1 a white color filter is installed, and at the output of the differentiating element

15 (plot e) a pulse appears which, arriving at the input of the key 16, translates it into a saturation state. At the output of the key 16 (plot g) there appears a pulse which, arriving at the reading input of the pulse counter, resets what is written in it. the number corresponding to the number of pulses received at its input in. the pulse duration from the output of the waiting multivibrator 12, to the decoder 14 and, since it will be less than eight, a single pulse does not appear at the output of the decoder 14 (plot C). The device analyzes the point under the information photodetector.

i + 1, i. As an example, under this. „Ditch is located between the photodetectors

and information carrier.

point is black spot diagrams

339602

The stresses are arranged similarly to the following. At the output of the comparator 11 (plot g), a pulse appears and from the counter of 13 pulses the number of pulses corresponding to the number of light filters minus one arrives at the input of the decoder 14, and as a result the output of the decoder 10 appears 14 the pulse corresponding to the presence of a black spot under the information photodetector 4. The concept is clearly accepted conditionally, it corresponds to the resolution of the photodetectors.

Thus, the accuracy of reading information is increased due to the fact that the device allows us to distinguish between black and colored spots.

Claims (1)

on the information carrier. Invention Formula A device for reading bar images on avt.ev. No. 1078447, characterized in that, in order to increase the reliability of reading, it contains a block of light filters mechanically connected with a stepping drive, a waiting multivibrator, a differentiating element, a key, a counter and a decoder, the output of which is the output of the device, and the input is connected to the output of the meter, the information input of the meter is connect. the output of the differentiating element is connected to the input of the key, the output of the waiting multivibrator is connected to the input of the differentiating element and to the input of the stepping drive, the light filter of the information carrier. t + -z4- F f f f i- / / Fig. I and. 5 ctpS5t (0) burn (pf C TPPPP ,. m „OPPpppppppd i-uiJ ff tpppppppppppppppppppppp 6TPPpppppppp Opppppppppp rt nirnnnfionnnnnnnno t and LcZIIIZIIin eLl. s1. fug. J Editor A. Vorovich Compiled by N. Milev Tehred V. Kadar Proofreader V. But Order 4225 / A1Tirage 672Subscription VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., d, 4/5 Production and printing plant, Uzhgorod, st. Project, 4 + + /./ .z iU : u g