JPS58130672A - Optical scanning device - Google Patents

Abstract

PURPOSE:To prevent the deterioration of print quality at a boundary part, by varying the boundary between the data recorded or displayed by each optical scanning system in response to a data pattern within an overlap region. CONSTITUTION:A boundary point retrieving part 11 decides the range to be recorded to the 1st and 2nd optical scanning systems by retrieving a data buffer memory which stores temporarily the recording data equivalent to a scanning line and then checking the data to be recorded to an overlap region. The 1st register 12 stores temporarily the delay time on the basis of the output signal of the part 11. As shown in the diagram, the boundary of the data to be recorded by each optical scanning system is decided between space data U, V, W and X (between V and W for example) which are produced most and continuously within an overlap region MN of a scanning range AN of the 1st optical scanning system and the range MC of the 2nd optical scanning system.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a modification of an optical scanning system used in an optical scanning device that is equipped with a plurality of optical scanning systems and scans by dividing a scanning line to record or display. .

(Technical background) As the speed of computers increases, the printing speed increases, and the number of printing machines required for single-processing systems or automatic design/drafting systems increases. The use of electronic writing* devices such as printers is rapidly expanding, but at the same time, the drawings handled by automated design and drafting systems (1#) are gradually becoming larger in size). It is becoming very large.

For this reason, in laser printers and the like, it is a current and overlapping technical problem to increase the size of drawings to be handled while reducing the size and weight of the printer.

0 Prior Art and Problems Figure 1 shows the scan @t2 divided and each divided scan 11
The optical system of the laser printer is shown in which the optical system of the laser printer is miniaturized by scanning and printing separately using 112 sets of optical scanning systems, in which l is a rotating polygon mirror, 2 is a first light source, and 3
The second light source %4 is emitted from the 1st U1 light beam 2"r7
11) modulator that modulates laser light with data, 5
6 is a second modulator that modulates the laser source with data, which is emitted from a second light source 3; 6 is a rotating polygon mirror modulated by the first modulator 4; A first lens condenses the laser beam reflected by f, which is modulated by a second modulator 5 and reflected by a rotating polygon mirror 1σ) located at the sixth position, and is reflected by a t-laser. a second lens for condensing light, 8
9 is a first reflecting mirror that reflects the laser beam focused by the first lens 6, and 9 is a second reflecting mirror that reflects the laser beam focused by the second astragalus 7.

First light 1l12, IEI modulator 4, and rotating polygon mirror 10
>The rotating reflector fo and the first lens 6 at the 0th position
and the first reflecting mirror 8 constitute an optical scanning system 14c1, and the fa
The second light source 3, the second variable 141h5, the sixth digit 1tK rotational reflection i1f of the rotating polygon mirror l, the second lens 7, and the second mirror 9 constitute a second optical scanning system.

2.As the rotating polyhedral boundary l rotates as shown by the arrow,
The j-laser light emitted from the first light source 2 scans the first scanning range AB of the scanning line 10 from A to BK, and at the same time the laser light emitted from the second light source 3 scans the first scanning range AB of the scanning line IO! If data is written by simultaneously scanning each scanning range B'C from B' to C, the modulation of the laser beam at the first modulator 4 or the second modulator 5 will be Starting σ) Since the dimming range varies irregularly, the pitch between the last pixel B in the first scanning range AFI and the first pixel B' in the second scanning range B/C is different from the normal pixel pitch. It becomes longer or shorter. Therefore, as shown in FIG. 2, the pitch between pixel B and pixel B' is better than that of normal pixels, and
If the data S of B' are all heated, a phenomenon occurs as if white data b was written between the image XB and the pixel B', and these various phenomena S continue. When this occurs, a white streak 5P force S occurs in the black pattern in the sub-scanning direction, which causes a problem in which the print quality is greatly reduced.

1) Purpose of the invention The present invention prevents the deterioration of print quality in the conventional example.
The purpose is to h.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The optical scanning method of the present invention includes a plurality of optical scanning systems, each optical scanning system overlaps a portion of the scanning lines, and scans the scanning lines in a shared manner, and records data on the scanning lines. In the display, the boundaries of the data recorded or displayed by each of the optical scanning systems are changed in accordance with the data padding within the overlap area, thereby preventing deterioration in print quality at the boundaries.

(g) Examples of the invention Next, the gist of the invention will be concretely explained using examples.

The MK3 diagram has two sets of optical scanning systems, a first and a second, and a scanning line 1.
&: A system block when the present invention is implemented in a router printer in which a 24g optical scanning system is used to scan the F9r electric length at the center of the scanning line while overlapping and record binary data. In the figure, reference numeral 11 searches a data buffer memory (not shown) that temporarily stores recording data for l scanning lines, and checks the data to be recorded in the overlap area. A boundary point search section determines the range to be recorded in the first optical scanning system, and determines the number of data to be recorded in the first optical scanning system and the last data of the data based on the output signal of the 12 boundary point search section 11. A first register that temporarily stores an address and a delay time from the start of scanning of the second optical scanning system to the start of modulation; A first delay circuit that provides a margin, 14 a @l counter that sets the modulation time of the first optical scanning system, and 15 a first operation that generates the address of data to be recorded in the first optical scanning system. 16 is a first modulation control unit that performs modulation control of the first optical scanning system; 7 is a unit that temporarily controls the number of data to be recorded in the optical scanning system of fa2 based on the output signal of the search unit 11; 18 is a second register for storing the J4 delay time from the start of scanning to the start of modulation of the second optical scanning system; 19 is a second delay circuit for setting the honey beak time of the second optical scanning system; 2 counters, 20 digits @ 2 second arithmetic unit that generates the r address of data to be recorded in the optical scanning system, 2;
1 is a second modulation control unit that performs modulation control tss of the second optical scanning system. Fig. 4 is a boundary point search unit l]σ] circuit block diagram,
Reference numeral 22 denotes a Thedabanopher memory that is the search target of the boundary point search unit 11, 23 a latch circuit that stores the previous bit 0)-7'-da, and 24 the data A and data AcJ)1 that are the search targets. A first comparator that compares data B before the bit with space data C as a reference for comparison, and generates an output signal D'ft when A=B:C, and an output signal E when A≠B or A+C. , 25 is a counter that starts counting when the first comparator 24 generates an output signal FJ' and resets the count when the first comparator 24 generates an output signal FJ'; 26 is the content F of the counter 25; 27 is a counter 25 which compares the contents G of the register described below and generates an output signal H when F) is G.
28 is an address counter that counts the address of the data to be searched, and 29 is an address that sets the value of the address counter 28 when the second comparator 26 generates the output signal H1-. This is a calculation unit that uses the contents of the register 27 and the address register 29 to determine the range of data to be recorded in the first and @2 optical scanning systems.

The above various configurations are shown in Figure 9 and F5.
Any of the space data tJ, v@W, or The area between them (for example, between V and W) is determined as the boundary of data recorded by each optical scanning system.

(Q. Effects of the invention and as explained by examples, according to the present invention,
When multiple optical scanning systems are used to scan and record or display data, each OJ nine scanning system crosses the boundary of the data to be recorded or displayed.
Depending on the data pattern within the knob area, it can be set, for example, to a portion where a large number of space data are consecutive. This prevents white stripes from appearing in the black pattern and degrading the recording quality.

[Brief explanation of the drawing]

Figure 1! Fig. 2 is an explanatory diagram of the wiring data and gutter 1 in the conventional example, AC is the scanner, AJ
The scanning range of JJ1, B'C is the second scanning range of all cities.
The figure is a circuit block diagram of a part of FIG. , MN indicates the toe, -lap region 1° 1st mouth 2nd figure yJ 3 ■

Claims (1)

[Claims] Il+ A device comprising a plurality of optical scanning systems, which scans a scanning line by assigning a -11t overlap name to each of the plurality of optical scanning systems, and records or displays data on the scanning line. An optical scanning method characterized in that boundaries of data to be arranged or displayed by each of the optical scanning systems are set according to a data pattern within the overlap area. 15. The optical scanning method according to claim 1, wherein the boundary of the data arranged and displayed by each optical scanning system is set in the space data section within the overlap area.