SU1368901A1 - Apparatus for reading graphic information - Google Patents

Abstract

This invention relates to automation and computing. The purpose of the invention is to increase the accuracy of the device. The device comprises an illuminator, a scanning unit, a focusing lens, a carrier cassette, a luminous flux conversion unit, a photoelectric unit, and a drive. The first and second photosensors, the sync pulse generator and the angular interferometer are introduced into the device. The light conversion unit has a camera and a light guide. The introduction of these elements makes it possible to reduce the nonlinearity of other elements of the device and thereby increase its accuracy. I zp f-ly, 3 ill. S with /)

Description

The invention relates to automation and computing, in particular to devices for reading graphic information.

The aim of the invention is to increase the accuracy of the device.

Figure 1 shows the layout of a device for reading graphic information; Fig. 2 is a schematic diagram of a luminous flux conversion unit; Fig. 3 is a functional diagram of a sync pulse generator.

The device has (FIG. 1) a cassette I for mounting the information carrier, an actuator 2 comprising a screw pair 3, an illuminator including a light source 4, a collimated light formation and flux block 5, a first rotating mirror 6, a scanning block 7 containing a scanning mirror 8 and corner reflectors 9 and 10, angular interferometer 11, focusing lens 12, second rotating mirror 13, light flux conversion unit 1A, photoelectric unit 15, first 16 and second 17 photosensors, synchro shaper 18, amplifier 19 and analog-to-ti The frame converter 20. The block 14 of the luminous flux conversion has (FIG. 2) a chamber 21 (side walls of the chamber not shown) containing a front wall with a specular surface formed by a second pivoting mirror 13, a rear wall 22 with a light-scattering inner surface, the bottom wall 23 with the diffusing inner surface, a scanning slit 24 formed by the lower edges of the rear and lower walls of the chamber, the upper wall 25 with the scattering surface, the entrance slit 26 formed by the upper edge of the back st APIS with the upper wall of the chamber, and the optical fiber 27 as a rigid polyhedron supported on the chamber side faces 28-31 which are made with the inner surface of the diffuser.

Shaper 18 clock pulses (fig.Z) contains the first amplifier 32, the first comparator 33, the first 34 and the second 35 inverters, the first 36 and second 37 triggers with a counting input, the second amplifier 38, the second comparator 39, the third 40 and fourth 41 inverters, the third 42 and fourth 43

triggers with a counting input, comparator 44, shaper 45 signals, first 1K flip-flop 46, first shaper 47 pulses, reversible counter 48, switch 49, second shaper 50 pulses, second 1K flip-flop 51 third 52 and second 53 elements And- NOT, the third driver

54 pulses, the element OR NOT 55, the first 56 and second 57 code switches, the first 58 and the second 59 elements 2I and the element OR 60.

The device works as follows.

The media is installed in the cassette 1, then by pressing a key on the remote (not shown) the cassette I using the drive 2 and screw

pairs 3 move under block 14

light flux conversion. The light emitted from the light source 4 is expanded by the collimated flux formation unit 5 and

is directed by the first pivoting mirror 6 to the scanning mirror 8 mounted on the rotor of the scanning unit 7. The oscillating rotor of the scanning unit 7 provides by

scanning mirror 8 scan the collimated beam in the scanning plane. The focusing lens 12, mounted so that its focal plane coincides with the plane

image, transfers the image of the tapping of the light source 4 into the image plane.

Thus, using the scanning unit 7, the focusing lens 12 and the second rotary mirror 13, a scan-line is formed in the image plane. vani consisting of successive positions of the image of dragging into

image planes.

The amplitude of oscillation is chosen so that the scan line crosses the first 16 and second 17

photosensors. Image modulated light flux is sensed by a light flux conversion unit 14 by a photoelectronic unit 15, the output of which is amplified by amplifier 19 and digitized by an analog-to-digital converter 20. Information is read from the entire image surface due to the optical deflection of the scanned beam within the line scanning along the x coordinate and moving the image carrier mounted in cash register 1 with the aid of the drive 2 (along the y coordinate). The position of the scanning beam on the scanning line is continuously monitored by the angular interferometer I1 using corner reflectors 9 and 10. The output signal (INT) is a sinusoidal signal, one period of which corresponds to the rotation of the scanning mirror through a certain angle.

The sync pulses accompanying the read information are generated by the synchro shaper 18 (FIG. 3).

Let the scanning spot move in the focal plane of the focusing lens 12 towards the first photo sensor 16. When the light spot crosses the input window of the photo sensor 16, it generates a pulse (LC), which is formed by the amplifier 32, the comparator 33 and the inverter FOR, and at the output of the inverter for the zero logic state, the triggers 42 and A3 are set to zero. The negative edge of the pulse (LK1) is calculated by trigger 36. The oscillation amplitude of the scanning unit 7 is chosen such that the length of the scanning line is 20-30 mm longer than the distance between the first 16 and second 17 photosensors. Therefore, some time after the photo sensor 16 intersects, the scanning spot is secondary, but in the opposite direction the research institute crosses this photo sensor. The negative edge of the second pulse (LK1) also podschittaets trigger 36, the output (T) which is formed by the front trigger podschitshaemy 37.Vsledstvie this to TC-A6 are set inputs of the flip-flop logic levels allowing the trigger A6 interferometer switching pulse generated by the comparator AA and shaper A5 , in the single position i The level of logical 1 from the output (C1) of the trigger 46 permits the passage of the generated interferometer pulses through the AND-NOT 52 element to the +1 input of the reversing counter 48. Reverse count The switch 48, the switch 49, the drivers 50 and 54, the element OR-NE 55 and the code switch 56 perform the functions of a programmable frequency divider, which determines, in accordance with the code set on the code switch 56, the period of the clock of the interferometer (c).

When the light spot crosses the second photo sensor 17, the first generated pulse (PC 1) sets the triggers 36 and 37 to zero position. As a consequence, the next interferometer pulse switches the trigger A6 to the zero position, removing the resolution from the input element AND-NOT 52. The negative front of this pulse switches on the counting input trigger 42 in a single position. The second pulse (PC 1) negative trigger switches the trigger 42 to the zero position. The negative front formed at the output (TH) switches the trigger 43 to the single position, thereby allowing the next interferometer pulse to set the trigger 51 to the single state. The logic level 1 from the output (C2) of the trigger 51 permits the passage of interferometer pulses through the element IS-HE 53 to the input -1 of the reversible counter 48. At the output (SI) of the block, the next sequence of clock pulses is formed. I

Thus, at the output (SR) of the synch pulse generator 18, sequences of sync pulses are formed corresponding to the movement of the scanning spot from the first photo sensor 16 to the second photo sensor 17, st, vice versa, from the photo sensor 17 to the photo sensor 16. Code switch 57, elements 2 and 58 and 59 and the OR 60 element provides the formation of a scan line sync signal (CTP) defining a significant sequence of sync pulses (c). Depending on the code set on the code switch 57, the sync signal (MFR) may correspond to the direction of movement of the scanning spot from the photo sensor 16 to the photo sensor 17 (forward stroke of the scanning spot), or, with a different code value, from the photo sensor 17 to the photo sensor 16 (reverse) or in both directions of movement of the scanning spot.

and angular interferometer,

Claims (1)

1. A device for reading graphic information comprising an optically coupled illuminator, a scanning unit, a focusing lens, a media holder fastening cassette, a luminous flux conversion unit and a photoelectronic unit whose output of the luminous flux contains a camcorder which is optically connected to the scanning unit, and the output is connected to the third information input of the sync pulse generator, 2, Device pop, 1, which differs from the fact that the unit is transformed and angular interferometer, The luminous flux contains a camera input which is optically connected with the scanning unit, and the output is connected to the third information input of the synch pulse generator, 2, The device pop, 1, differs from the fact that the unit is converted go is an information output of the device, a drive mechanically connected to the carrier attachment cassette, characterized in that, in order to increase the accuracy of the device, it contains the first and second photosensors optically connected with the focusing lens and located in its focal plane on the edges the scan lines, the sync pulse generator, the first and second information inputs of which are connected respectively to the first and second photosensors, and the outputs are synchronizing outputs of the device, internal overhnost front wall which vtolnena mirror and the side, rear and bottom - light- scattering, the lower edge the back and bottom walls form a scanning slit, and the top edges of the rear wall with the top wall with a light-scattering surface form the entrance slit of the chamber, and the light guide in a rigid polyhedron attached to a chamber, the lower face of which is the upper wall of the chamber, and the lateral faces are made with a light-scattering inner surface. // FIG. 25 Z3 FIG. 2 Fig.Z