JPS60120658A - Picture magnification varying method of semiconductor laser - Google Patents

Abstract

PURPOSE:To attain magnification and reduction with high print quality by changing the scanning speed of light beam and also changing the luminous intensity of a semiconductor laser to apply printing of a character with variable power. CONSTITUTION:In magnifying a character, since the light beam in the main scanning direction is continuous, the time lighting the semiconductor laser 1, that is, a modulating frequency is varied electrically to expand easily the spot width. Variable power is attained by changing the number of turnings of a polygon deflector 2 in the subscanning direction by means of a motor driver 12 or changing the speed of a photosensitive body 4 to change the scanning speed. Then a nonscanning part A is caused with a constant beam diameter. Thus, the spot diameter of the laser beam is increased so as not to cause the part A and pack character dots completely. The laser current value is changed to change the luminous intensity in order to change the spot diameter.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention deflects and scans a half-91 Holley beam onto a photoconductor using a polygon, r scanner, etc.
There is a recording of line 4 f C 1 ablink [this J-;

Conventional example of 114 configuration and its problems Two-dob [Ru 1
) C1F printers using low-cost semiconductor lasers have been used as terminal printers and the like.

Conventionally, in Sea 1 Aburinta, to change the size of the letters (well, the kanji corresponding to each size) Δan 1 ~
I prepared J3, selected - (kanji) A1~ according to the size of the letters, and printed them out using IR. For this reason, it was necessary to use - (kanji) A to correspond to the size of the kanji, and the phono 1 to memory became bulky, causing the device to become larger and more expensive. Purpose of the present invention (3), to solve the above-mentioned conventional drawbacks.
It is an object of the present invention to provide an image magnification method that can be performed using an Azolinta recording optical system.

In order to achieve the objective of ``Configuration of the Invention'' (1), the image scaling method of the present invention includes the following:
Depending on the magnification of the recorded image -Q'l emitted from the C1 semiconductor laser
There is a configuration C in which C recording is performed by changing the intensity of the light beam and the scanning speed.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

Figure 1 (schematic diagram of the semiconductor laser printer)
1 is a semiconductor laser C', and the optical heath emitted from this semiconductor laser 1 is a :1 remeter lens (shown in the figure).
! 2), is deflected by a polygon deflector 20, and scanned on a photoreceptor 4 via an imaging lens 3. Around the photoreceptor there is a charger 5 and a developing window 6.
i7j(i)? , Ii Z 7, al J, a hiklininking means 8 is provided, and the recording latent image on the conductor ray 1 21' is converted into a stomach 1 image by the developing device 4, and 'l'/
;')"lj It is transferred to the concave paper 9 by the electric device 7, and the recording is completed after passing through the constant means (centroid μsu゛). 10 is:
1', W type - Drive control circuit of Lie '1 C1 Character fan A
(In addition, 16 is used to modulate the light beam output intensity of the tray 1. 12 is used to change the rotational speed of the polygon deflector 2, that is, the scanning speed of the light beam. be.

2nd figure number, 1. Shows the scanning state in the Rayleigh light:
It is b. The main scanning direction is the direction scanned by the polygon deflector 33, and is the sub-scanning direction, ta, and the rotation direction of the photoreceptor 4. Here Beamsbot 1- forms 114 letters 1~tsu1~.

Figure 3 shows scanning when enlarging characters G and L! ,
,: something. In this case, since the light beam in the main scanning direction (1) is continuous, the semiconductor laser "1" is stippled.
By electrically changing the modulation frequency by 1, the sub-board width can be easily expanded. on the other hand,
The sub-scanning direction can be changed by changing the rotation speed of the polygon deflector 2 using the Tanabata drive unit 412 or by changing the speed of the photoreceptor 1;
Then, perform change 18 by changing the scanning speed.

Figure 3 shows a state in which the sub-scanning direction has been enlarged.
be. However, in this case, if the diameter of the laser beam spoiler 1 is constant, the distance between adjacent scanning lines in the sub-scanning direction will not be large and a non-scanning portion A will occur. As a result, gaps occur between the dots of characters, resulting in print quality of 4j.
＜It becomes.

In FIG. 4, the diameter of the slot 1 of the laser beam 11 is made smaller in order to improve this drawback. 3 for text magnification
4. Accordingly, increase the beam spot diameter so that the space between the letters 1-21 is completely filled.

FIG. 5d3 and FIG. 6 show one method of changing the position of the laser beam spot #-diameter. As shown in the figure, when the current value of the semiconductor laser is changed, the optical output of the laser changes.The light output from the laser beam 11 is generally a spot with a Gaussian-shaped light intensity distribution, so the optical output is changed by J. A spora 1 to 11 whose diameter is changed is formed. That is, when the driving current of the semiconductor laser 1 is greatly increased from a to b,
The intensity of the output IJ'' beam increases from al to bl7
11. At this point, the intensity distribution of the light beam spot 1 on the photoreceptor 4 corresponding to the output intensity of the laser beam [
If we write the lowest value of the amount of light developed by C1 photoreceptor 4 in a Gaussian shape as shown in FIG. The diameter is al
It will be expanded from B3 to B3. Therefore, by increasing or decreasing the driving current of the semiconductor laser 1, the diameter of the optical beam spot I can be changed in size.

The circuit that realizes this is shown in Figure 79. FIG. 7 shows a drive control circuit 10 for the semiconductor laser 1. Current flows through the transistor Q1 in response to an image signal from the character font memory 11 input to the terminal 13, and a light beam is emitted from the semiconductor laser "1. When the light beam diameter switching signal input to the terminal 14 is turned on in order to increase the light beam diameter in the current state, current flows through the transistor Q2 and is added to the drive current of the semiconductor laser 1, so that the light beam diameter is increased. On the other hand, when the light beam diameter switching signal is turned off, no current flows through transistor Q2, so the light beam diameter becomes smaller. Therefore, if you set the smaller light beam diameter in advance, , large and small light beam diameters can be easily obtained by simply switching. Note that R1 and R2 are resistors.

When the diameter of the light beam of the semiconductor laser 1 is increased in this way, the rotational speed of the polygon deflector 2 is recorded as slow<t,'r by the motor control device 10, and the diameter of the light beam is made small. By recording the rotational speed of the polygon deflector 2 by combing the polygon deflector 2, the enlargement and reduction can be done simply by 1;
Cost reduction becomes possible.

As described in detail, according to the present invention, when the character is changed by the printer, when the scanning speed of the light beam is changed, the light intensity of the semiconductor relay is changed to 1 and 2. <[To change the J, Su, 1rh printed product ¥! The expansion and contraction of l is I
II 111. Therefore, one type of character saisu is sufficient for the character ゛)Ant, and miniaturization and low -1 stroke are
Noh roars.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram of a printer according to an embodiment of the present invention.
FIG. 3 is an explanatory diagram of the state enlarged in the direction of [61 sub-scanning], FIG. 1 is an explanatory diagram of the enlarged state, and FIG. 5 is an explanatory diagram of the semiconductor relay An explanatory diagram of the relationship between the initial current and the intensity of Rayleigh beam.
FIG. 7 is a circuit diagram C of the driving circuit of the Ihor laser. 1... Semiconductor 1 nori, 2... Polygon deflection λ;
, /1...Photoconductor, 10...PJI ip1 control circuit, 11...Character font memory, 12...Motor drive device agent Yoshihiro Moriki Figure 1 Figure 2 Otori ■1 Figure 3 Figure 4

Claims (1)

[Claims] ゛1. An image magnification method for a semiconductor 1 norli printer that performs recording by changing the intensity scanning speed of a light beam emitted from a -C1'I' state-of-the-art relay according to the magnification of a recorded image 1 (Q).