Radiant energy – Photocells; circuits and apparatus – Housings
Reexamination Certificate
2000-12-11
2003-04-08
Le, Que T. (Department: 2878)
Radiant energy
Photocells; circuits and apparatus
Housings
C250S234000
Reexamination Certificate
active
06545266
ABSTRACT:
BACKGROUND OF THE INVENTION
This application incorporates by reference Taiwanese application Serial No. 089217702, Filed on Oct. 12, 2000.
1. Field of the Invention
The invention relates in general to a photo-sensing apparatus, and more particularly to an optical module, which can be calibrated at least in four directions.
2. Description of the Related Art
The advance of hi-technology recently is leading the revolution of electric equipment and appliance such as computers, computer peripherals, and multi-functional peripherals. For example, scanners are developed to have resolution up to 1200 dpi and 9600 dpi. Besides higher quality, cost down is also an important issue for the scanner manufactures to be competitive.
Most commercial scanners apply charge couple device (CCD) as a photo sensor to sense the light reflected from the to-be-scanned document. In order to obtain a better image, the path of the reflected light should be perpendicular to the surface of the optical module. Thus, the position of the CCD module should be adjustable precisely to increase the scanning quality.
FIG. 1A
shows the ideal relative position of the CCD module and the path of the light. The ideal position of the CCD module and the path of the light are perpendicular to each other. Herein, the CCD module
100
is located parallel to YZ plane and the light is moving along the X axis.
The CCD module
100
is typically assembled with a carriage. The CCD module
100
and the carriage together form an optical module. The misalignment of the CCD module
100
during the assembling process is hard to avoid. Thus, adjusting the CCD module is an important step after assembly. The orientation of the CCD module
100
is generally designed to be able to move along the Z axis (as shown in FIG.
1
B), to move along the Y axis (as shown in FIG.
1
C), to rotate on the X axis (as shown in FIG.
1
D), to rotate on the Z axis (as shown in FIG.
1
E), and to move along the X axis (as shown in FIG.
1
F).
Three-direction and five-direction adjustable optical modules are two conventional designs. The CCD module of the conventional three-direction adjustable optical module can be manually adjusted to have the movements like moving along the Z and Y axes and rotates on the X axis. The optical module of the conventional three-direction adjustable optical module can be further adjusted by focusing the lens along the X axis.
The CCD module of the five-direction adjustable optical module, with the aid of extra devices, has the movements like moving along the X, Y, and Z axes and rotating on the X and Z axes.
The conventional three-direction adjustable optical module
200
is illustrated in
FIG. 2
, which includes a carriage
210
with a coupling window
210
a
, and a CCD module
220
. The coupling window
210
a
has a screw hole
240
. The CCD module
220
and the carriage
210
can be connected by using screws
230
to penetrate the CCD module
220
and fix in the screw hole
240
of the coupling window
210
a.
The conventional three-direction adjustable optical module
200
has the advantage of low cost since three-direction adjustment can be easily obtained by simple design. For the purpose of further cost down, the carriage
210
is typically made of plastics. However, the process of plastic formation tends to cause flaw on the carriage
210
. If the coupling window
210
a
is made not parallel to the YZ plane, the CCD module
220
fixed thereon can not be parallel to the YZ plane, neither. Since the conventional three-direction adjustable optical module
200
is not able to rotate on the XZ axis, the CCD module
220
can not be calibrated. It is therefore apparent that the image quality will be greatly effected.
A five-direction adjustable optical module, as shown in
FIG. 3
, was then proposed. The conventional five-direction adjustable optical module is able to move along the X, Y, and Z axes and rotate on the X and Z axes. As shown in
FIG. 3
, the conventional five-direction adjustable optical module
300
includes a carriage
310
, CCD module
320
, device
330
, device
340
and device
350
. The CCD module
320
is indirectly connected to the contact window
310
a
of the carriage
310
and there are the device
330
, device
340
, and device
350
sequentially between the carriage
310
and the CCD module
320
. The CCD module
320
is calibrated by the combination of the device
330
, device
340
, and device
350
under the control of a calibration program rather than manual control. However, it is apparent that the five-direction adjustable optical module
300
needs more devices and is more complicated so that the cost thereof is rather high and is therefore less competitive in the market.
To sum up, the conventional optical module has the following disadvantages:
1. the CCD module of the conventional three-direction adjustable optical module can not rotate on the Z axis; thus, the calibration result can not be optimized; and
2. the conventional five-direction adjustable optical module is less competitive in the market, regarding the cost and price.
SUMMARY OF THE INVENTION
It is therefore an object of the invention to provide a four-direction adjustable optical module, which is based on a three-direction adjustable optical module and is further modified to rotate on the Z-axis. Hence, the four-direction adjustable optical module of the invention is simple in structure but can be calibrated in at least four directions.
According to the object of the invention, a four-direction adjustable optical module including a carriage and a CCD module is disclosed. The carriage includes a coupling window for coupling with the CCD module. Each of the two sides of the CCD module includes a screw hole and an elastic device. The elastic device slightly protrudes from the surface of the coupling window. While the CCD module and the coupling window are coupled, screws are employed to screw through the CCD module and into the screw holes of the coupling windows. Therefore, the elastic devices deform by the stress from the CCD module. By adjusting the tightness of the screws, the orientation of the CCD module rotating on the Z axis can be calibrated. Thus, the adjustable optical module of the invention can be calibrated at least in four directions.
REFERENCES:
patent: 6473205 (2002-10-01), Pepe
Lung Chen
Yi Lee Ta
Le Que T.
Rabin & Berdo P.C.
Silitek Corporation
LandOfFree
Four-direction adjustable optical module does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Four-direction adjustable optical module, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Four-direction adjustable optical module will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3111941