JPH05212899A - Laser printer - Google Patents

Abstract

PURPOSE:To provide a laser printer that can perform the print suitable for each of high density and high speed by switching the diameter of a beam in accordance with the print mode. CONSTITUTION:A lens 11 that makes a laser beam narrow or wide is placed in and out by a solenoid 12 so that the diameter of the beam is set suitable for each of high density print and high speed print. In high density printing, the beam diameter adjustment lens 11 is placed out to narrow the diameter of the beam, thereby the high density print can be obtained. In high speed printing, the solenoid 12 is not activated so that the lens 11 is placed in by a spring to widen the diameter of the beam to a comparatively wide width suitable for a high speed print, thereby the high speed print can be obtained. Consequently, the diameter of the beam suitable for each of high density print and high speed print can be obtained with a simple structure, thus performing a high quality print.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to, for example, a laser printer device which switches between high-definition printing and high-speed printing.

[0002]

2. Description of the Related Art FIG. 5 shows, for example, JP-A-63-204226.
FIG. 3 is a cross-sectional view showing a conventional laser printer device disclosed in Japanese Patent Laid-Open Publication No. JP-A-2003-187, in which 1 is a semiconductor laser, 2 is a slit, 3 is a polygon mirror, 4 is a photosensitive drum, and 5 is a photosensitive drum.
Is a lens A, 6 is a lens B, 7 is a reflecting mirror, 8 is a capstan, and 9 is a motor.

Next, the operation will be described. In FIG. 5, the laser printer device is such that a laser beam is emitted from a semiconductor laser 1 as a light source and a slit 2
The beam diameter is controlled by, and the polygon mirror 3 scans the photosensitive drum 4 in the axial direction. The laser beam scanned by the polygon mirror 3 passes through the lens A of 5,
After passing through the lens B of No. 6, it is guided to the reflection mirror 7. The beam is applied to the photosensitive drum 4 to form a latent image on the photosensitive drum 4. The slit 2 can be driven by a capstan 8 on the motor shaft, and the size of the slit can be changed by rotating the motor 9 according to a command from a control device (not shown). With such a configuration, when the print density changes, the motor 9 is driven to move the slit 2 and change the slit width so that the beam diameter can be adjusted according to the print density.
Incidentally, as a similar idea, Japanese Patent Laid-Open No. 63-31270
There is a bulletin.

As another method, a collimator lens is arranged at the position of the slit 2 and the collimator lens is moved in the optical axis direction to change the beam diameter, which is disclosed in JP-A-60-67920.
JP-A-60-68317, JP-A-60-
There is 100111 publication. In this method, the spot diameter is changed by moving the collimator lens in the optical axis direction, but there is a problem in that the beam diameter is not stable due to a slight difference in distance or deviation of the optical axis.

[0005]

Since the conventional laser printer device is constructed as described above, the shape of the slit and the positioning of the collimator lens must be processed with high precision, and the assembling can be performed with high precision. However, there is a problem that the beam diameter is not stable.

The present invention has been made in order to solve the above problems, in which high-speed printing is performed by irradiating a laser beam with a large spot diameter while high-density printing is performed with a small spot diameter. It is an object of the present invention to provide a laser printer device capable of irradiating a laser beam with a laser beam and changing the spot diameter easily with a simple structure.

[0007]

A laser printer device according to the first invention is one in which a lens is inserted or exchanged in order to change the laser beam diameter in the laser optical path.
It has the following elements. (A) Laser light source for generating laser beam light (b) Laser light path forming means for forming a laser light path having a predetermined path using the laser beam light generated by the laser light source, (c) Laser light path forming means A diameter changing means that is provided at an arbitrary position of the laser optical path formed by and changes the beam diameter of the laser beam light.

A laser printer device according to a second aspect of the present invention has a plurality of laser light sources arranged and gathered on the same optical axis to select or simultaneously use the laser light sources, and has the following elements. (A) A plurality of laser light sources that generate laser beam lights having different beam diameters; (b) Align the optical axes of the laser beam lights generated from the laser light sources to form a laser optical path having a predetermined path. Laser light path forming means, (c) laser light source selecting means for selecting one or more laser light sources for sending laser beam light to the laser light path formed by the laser light path forming means.

[0009]

In the laser printer device according to the first aspect of the invention, the laser beam diameter is changed by narrowing or widening the laser beam by inserting or exchanging a lens to change the laser beam diameter in the laser optical path. A relatively large beam diameter suitable for printing or a relatively small beam diameter suitable for high-density printing can be used.

Further, in the laser printer device according to the second aspect of the present invention, the same operation as described above can be obtained by arranging a plurality of laser light sources and selecting the laser light sources so as to collect them on one optical axis. In this case, fine printing can be realized by operating the laser light sources at the same time and sending normal character print data to the one with a larger spot diameter and sending gradation data such as a photograph to the one with a smaller spot diameter.

[0011]

【Example】

Example 1. An embodiment of the first invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing a printer device showing one embodiment of the present invention. In FIG. 1, 1 is a semiconductor laser, 3 is a polygon mirror, 4 is a photosensitive drum, and 5 is a photosensitive drum.
Is a lens A, 6 is a lens B, 7 is a reflection mirror, 10 is a beam diaphragm lens, 11 is a beam diameter adjusting lens, and 12 is a solenoid.

Next, the operation will be described. In FIG. 1, a laser printer device is irradiated with laser beam light from a semiconductor laser 1 as a light source, a beam diameter is narrowed by a beam diaphragm lens 10, and a polygon mirror 3 scans the photosensitive drum 4 in an axial direction. .. Polygon mirror 3
The laser beam scanned at is passed through the lens A of 5, the lens B of 6, and is guided to the reflection mirror 7. The beam is applied to the photosensitive drum 4 to form a latent image on the photosensitive drum 4. The beam diameter adjusting lens 11 is, for example, when the beam diameter of the beam diaphragm lens 10 is set to a small beam suitable for high density printing,
By inserting the beam diameter adjusting lens 11, the beam is expanded so that high-speed printing can be realized. In this example, the beam diameter adjusting lens 11 has a solenoid 1
The beam diameter adjusting lens 11 is inserted into the optical axis or retracted outside the optical axis by engaging the two.

With such a structure, when performing high-density printing, the beam diameter adjusting lens 11 is retracted by the operation of the solenoid 12 to have a small beam diameter, and high-density printing is performed. When performing high-speed printing, the solenoid 12 is deactivated, and a spring (not shown) acts to insert the beam diameter adjusting lens 11 so that a relatively large beam diameter suitable for high-speed printing is achieved and high-speed printing is performed.

In the above description, the beam is expanded by inserting the beam diameter adjusting lens 11, but
It is obvious that the present invention can be implemented even if the beam diameter is set to a diameter suitable for high-speed printing by the beam stop lens 10 and the beam is adjusted by inserting the beam diameter adjusting lens 11.

Example 2. Next, another embodiment of the first invention will be described with reference to the drawings. FIG. 2 is a sectional view showing a printer device according to one embodiment of the present invention. In FIG. 2, 1 is a semiconductor laser, 3 is a polygon mirror, 4 is a photosensitive drum, 5 is a lens A, and 6 is a lens B. , 7 is a reflection mirror, 8 is a capstan, 9 is a motor, 10A, 10
B and 10C are beam diaphragm lenses, and 13 is a mounting plate.

Next, the operation will be described. In FIG. 2, the laser printer is irradiated with laser beam light from a semiconductor laser 1 as a light source, a beam diameter is narrowed by a beam diaphragm lens 10A, and a polygon mirror 3 is used.
The photosensitive drum 4 is scanned in the axial direction. The laser beam scanned by the polygon mirror 3 passes through the lens A 5 and the lens B 6 and is guided to the reflection mirror 7. The beam is applied to the photosensitive drum 4 to form a latent image on the photosensitive drum 4. The beam diaphragm lens 10A has, for example, a beam diameter of a small beam suitable for high-density printing. The beam diaphragm lens 10B is
It is a medium beam suitable for ordinary printing. The beam diaphragm lens 10C has a relatively large beam suitable for high-speed printing. This beam diaphragm lens 10A, 10B, 1
0C is attached to a disc-shaped attachment plate 13, and each lens can be arranged on the laser optical axis by rotating. The capstan 8 provided on the shaft of the motor 9 is engaged with the periphery of the mounting plate 13 so that the mounting plate 13 is rotated by the rotation of the motor 9. Beam stop lens 10
It can be selected by arranging A, 10B and 10C on the concentric circles of the mounting plate 13 so as to be on the optical axis of the laser beam.

With this configuration, when performing high-density printing, the beam diaphragm lens 10A is selected by rotating the motor 9 by a control signal (not shown) to perform high-density printing. Similarly, for ordinary printing and high-speed printing, the beam diaphragm lens 10B. It is obvious that this can be realized by selecting each of 10C.

In the above description, the selection of the three lenses of the beam diaphragm lenses 10A, 10B and 10C has been described for convenience of description, but it is obvious that the present invention is not limited to the number and can be applied to two or more selections.

Example 3. Next, another embodiment of the first invention will be described with reference to the drawings. FIG. 3 is a sectional view showing a printer device showing one embodiment of the present invention. In FIG. 3, 1 is a semiconductor laser, 3 is a polygon mirror, 4 is a photosensitive drum, 5 is a lens A, and 6 is a lens B. , 7 is a reflection mirror, 8 is a capstan, 9 is a motor, 10A, 10
C is a beam diaphragm lens, and 13 is a mounting plate.

Next, the operation will be described. In FIG. 3, the laser printer apparatus is irradiated with laser beam light from a semiconductor laser 1 as a light source, a beam diameter is narrowed by a beam diaphragm lens 10A, and a polygon mirror 3 is used.
The photosensitive drum 4 is scanned in the axial direction. The laser beam scanned by the polygon mirror 3 passes through the lens A 5 and the lens B 6 and is guided to the reflection mirror 7. The beam is applied to the photosensitive drum 4 to form a latent image on the photosensitive drum 4. The beam diaphragm lens 10A has, for example, a beam diameter of a small beam suitable for high-density printing. The beam diaphragm lens 10C has a relatively large beam suitable for high-speed printing. The beam diaphragm lenses 10A and 10C are attached to a rectangular mounting plate 13, and each lens can be arranged on the laser optical axis by linearly moving. The capstan 8 provided on the shaft of the motor 9 engages with one side of the mounting plate 13, and the mounting plate 13 moves linearly as the motor 9 rotates. It can be selected by arranging the beam diaphragm lenses 10A and 10C on the straight line of the mounting plate 13 so as to be on the optical axis of the laser beam.

With this configuration, when performing high-density printing, the beam diaphragm lens 10A is selected by rotating the motor 9 by a control signal (not shown) to perform high-density printing. Similarly, for high speed printing, the beam diaphragm lens 10C
It is clear that this can be achieved by selecting.

In the above description, the selection of the two lenses of the beam diaphragm lenses 10A and 10C has been described for convenience of description, but it is obvious that the present invention is not limited to the number and can be applied to two or more selections.

As described above, in the first to third embodiments, the laser spot diameter is set at an arbitrary position of the laser light path in the printer device including the laser light source, the lens system forming the laser light path, and the laser beam deflection scanning device. The laser printer device has been described which is characterized in that the lens is switched for the purpose of changing. In particular, in the first embodiment, as the diameter changing means for changing the laser spot diameter, the laser printer device has been described which is characterized in that an additional lens is inserted at an arbitrary fixed position in the laser optical path. In the second embodiment, as the diameter changing means,
The laser printer device has been described in which the lens is rotated and switched to an arbitrary fixed position in the laser optical path. Further, in the third embodiment, as the diameter changing means, the laser printer device is described which is characterized in that the lens is linearly switched to an arbitrary fixed position of the laser optical path.

Example 4. Next, an embodiment of the second invention will be described with reference to the drawings. FIG. 4 is a sectional view showing a printer device showing one embodiment of the present invention. In FIG. 4, 1A and 1B are semiconductor lasers, 3 is a polygon mirror, 4 is a photosensitive drum, 5 is a lens A, and 6 is a lens. Lens B,
Reference numeral 7 is a reflection mirror, and 14 is a half mirror.

Next, the operation will be described. In FIG. 4, the laser printer is irradiated with laser beam light from a semiconductor laser 1A as a light source, and is scanned in the axial direction of the photosensitive drum 4 by the polygon mirror 3 passing through the half mirror 14. The laser beam scanned by the polygon mirror 3 passes through the lens A of 5, passes through the lens B of 6, and is guided to the reflection mirror 7. The beam is applied to the photosensitive drum 4 to form a latent image on the photosensitive drum 4. The semiconductor laser 1A has, for example, a beam diameter of a small beam suitable for high-density printing. The semiconductor laser 1B has a relatively large beam suitable for high-speed printing. The beam of the semiconductor laser 1B is reflected by the half mirror 14 and adjusted so as to reach the polygon mirror 3 according to the optical axis of the beam of the semiconductor laser 1A. With this configuration, switching between high-density printing and high-speed printing can be performed with the semiconductor lasers 1A and 1B.
It can be done by switching.

In the above description, the two semiconductor lasers 1A and 1B are switched for convenience of description, but the number is not limited and it is obvious that the invention can be applied to two or more selections. ..

Example 5. Semiconductor laser 1A in Example 4
Although it was explained that the two semiconductor lasers 1 and 1B are selectively switched, the semiconductor lasers 1A and 1B are simultaneously operated, and the halftone such as a photographic print is dithered by the spot diameter of the semiconductor laser 1A. If the semiconductor laser 1B is used for character printing, high-quality printing can be performed.

As described above, according to the fourth embodiment, in the printer device constituted by the laser light source, the lens system for forming the laser beam path, and the laser beam deflection scanning device, a plurality of laser beams are provided on the same optical axis at arbitrary positions in the laser beam path. A laser printer device has been described which is characterized by changing the laser spot diameter by collecting the laser light sources and selecting the laser light source. Further, in the fifth embodiment, a laser printer device is described in which a plurality of laser light sources are simultaneously operated to perform printing with different print densities.

[0029]

As described above, according to the first invention, since the diameter of the laser beam is changed, high-density printing and high-speed printing can be reliably switched, and at the same time, the positioning of the lens can be performed. Other than that, there is an effect that the device can be made simple and inexpensive, and that a highly accurate device can be obtained.

Further, in the second invention, the semiconductor laser 1
Since it is configured to selectively operate a plurality of semiconductor lasers such as A and 1B, high-density printing and high-speed printing can be reliably and immediately switched, and at the same time, the device can be inexpensive and the accuracy can be improved. There is an effect that a high price can be obtained. Further, if a plurality of semiconductor lasers 1A and 1B are simultaneously operated, high-quality printing can be easily performed.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a laser printer device according to an embodiment of the first invention.

FIG. 2 is a sectional view showing a laser printer device according to another embodiment of the first invention.

FIG. 3 is a sectional view showing a laser printer device according to another embodiment of the first invention.

FIG. 4 is a sectional view showing a laser printer device according to an embodiment of the second invention.

FIG. 5 is a cross-sectional view showing a conventional laser printer device.

[Explanation of symbols]

 1 Semiconductor Laser 2 Slit 3 Polygon Mirror 4 Photosensitive Drum 5 Lens A 6 Lens B 7 Reflecting Mirror 8 Capstan 9 Motor 10 Beam Aperture Lens 11 Beam Diameter Adjusting Lens 12 Solenoid 13 Mounting Plate 14 Half Mirror

Claims (2)

[Claims] 1. A laser printer device having: (a) a laser light source for generating a laser beam;
(B) a laser optical path forming means for forming a laser optical path having a predetermined path by using the laser beam light generated from the laser light source, (c) at a predetermined position of the laser optical path formed by the laser optical path forming means Diameter changing means provided to change the beam diameter of the laser beam light. 2. A laser printer device having the following elements: (a) a plurality of laser light sources for generating laser beam light having different beam diameters; (b) an optical axis of each laser beam light generated from the laser light source. Match
A laser light path forming means for forming a laser light path having a predetermined path; and (c) a laser light source selecting means for selectively operating the laser light source for sending a laser beam light to the laser light path formed by the laser light path forming means.