CN100533465C - Scanning methods that improve scan quality - Google Patents

Abstract

The method includes following steps: setting up a prearranged relative displacement between a file and a scanning module; making relative stable standstill between the file and the scanning module; turning on light source to illuminate the file, and receiving signals of stable image from the file by using an image sensor in the scanning module; stopping operation of the image sensor after lasting out a period of prearranged time and receiving signals of stable image, and turning the light source off. The invented method prevents harmful effect on scanning quality caused by vibration of file relative to scanning module.

Description

Scanning methods that improve scan quality

technical field

The invention relates to a scanning method which can improve the scanning quality, in particular to a scanning method which can avoid the adverse effect on the scanning quality caused by the vibration of the document relative to the scanning module.

Background technique

The scanning method used by the traditional scanning device usually starts to expose the image sensor when the scanning module is moved, or starts to expose the image sensor when the document is transmitted, so as to speed up the scanning speed. That is to say, for the flatbed scanner, during the period when the scanning module starts to move the distance of one scanning line, the internal image sensor starts to receive the light signal from the document until it lasts for a predetermined period of time. On the other hand, for the sheet-fed scanner, the internal image sensor receives the light signal from the document until the document moves for a predetermined period of time.

Figure 1 shows a known graph of the position of the scanning module versus the exposure time. As shown in FIG. 1 , the period during which the file moves from position D1 to position D2 is exactly from T1 to T2 , and the period from T2 to T3 is when the file is really completely still. The traditional scanning exposure period is exactly the period from T1 to T3 (shown by the hatched area). However, due to the limitations of the mechanical structure, for example, the file or scanning module of a general scanner is driven by a stepper motor, and even the finer stepper motor still has an unstable state from stationary to active or to stationary. Make the file in a state of vibration between T1 and T2. The scanning exposure performed under the vibrating state of the document will definitely affect the scanning quality. This phenomenon is gradually unacceptable by users under the condition that the requirements for scanning quality become more and more stringent.

Contents of the invention

Therefore, an object of the present invention is to provide a scanning method that can improve scanning quality.

Another object of the present invention is to provide a scanning method in which a user can select a normal quality scanning mode and a high quality scanning mode.

In order to achieve the above object, the present invention provides a scanning method capable of improving scanning quality, comprising the following steps: (a) causing a predetermined relative displacement between a document and a scanning module; (b) making the document relative to the scanning module Stable still; (c) turn on a light source to illuminate the document, and use an image sensor of the scanning module to receive a stable image signal from the document; and (d) continue receiving the stable image signal for a first predetermined period of time Afterwards, the receiving action of the image sensor is stopped, and the light source is turned off.

To achieve the above object, the present invention also provides a scanning method that can improve scanning quality, comprising the following steps: (a) continuously turning on a light source to illuminate a document; (b) making the document and a scanning module generate a predetermined Relative displacement, while using an image sensor of the scanning module to discard an unstable image signal from the document; (c) Make the document and the scanning module relatively stable and stationary, and use the image sensor of the scanning module to receive signals from the document and (d) stop the receiving action of the image sensor after receiving the stable image signal for a first predetermined period of time. In addition, the present invention also provides a scanning method for the user to select a scanning mode.

In this way, it is possible to avoid adverse effects on the scanning quality caused by the vibration of the document relative to the scanning module.

Description of drawings

Fig. 1 shows the relation figure of the position of known scanning module and exposure time;

Fig. 2 shows the relation figure of the position and exposure time of the scanning module of the present invention;

FIG. 3 shows a flowchart of a scanning method according to a first embodiment of the present invention;

FIG. 4 shows a flowchart of a scanning method according to a second embodiment of the present invention;

5 shows a flowchart of a scanning method according to a third embodiment of the present invention;

FIG. 6 shows a flowchart of a scanning method according to a fourth embodiment of the present invention.

Detailed ways

FIG. 2 shows the relationship between the position of the scanning module and the exposure time of the present invention. As shown in FIG. 2 , the period during which the file moves from position D1 to position D2 is exactly from T1 to T2 , and the period from T2 to T3 is when the file is really completely still. The scanning exposure period of the present invention is exactly the period from T2 to T3 (shown by the hatched area). Since the period from T2 to T3 is a relatively stable period for the document and the scanning module, stable image quality can be obtained.

It should be noted that although the file location is used for illustration, those skilled in the art should easily understand that the location of the scanning module can also be used as the basis for implementation.

FIG. 3 shows a flowchart of a scanning method according to a first embodiment of the present invention. As shown in Figure 3, the scanning method of the present embodiment comprises the following steps:

Step S1: start;

Step S4: driving a document or a scanning module to cause a predetermined relative displacement between the document and the scanning module;

Step S5: Make the file and the scanning module relatively stable and static;

Step S6: Turn on a light source to illuminate the document, and use an image sensor of the scanning module to receive a stable image signal from the document;

Step S7: Stop the receiving action of the image sensor after receiving the stable image signal for a first predetermined period of time, and turn off the light source; and

Step S8: end.

It should be noted that steps S4 to S7 can be repeated until all scanning lines are scanned.

In this embodiment, the light source must be able to be turned on or off quickly to achieve a stable light source, such as a light emitting diode.

FIG. 4 shows a flowchart of a scanning method according to a second embodiment of the present invention. As shown in Figure 4, the scanning method of the present embodiment comprises the following steps:

Step S1: start;

Step S4': Continuously turn on a light source to illuminate a document;

Step S5': driving the document or a scanning module to cause a predetermined relative displacement between the document and the scanning module, and simultaneously using an image sensor of the scanning module to discard an unstable image signal from the document;

Step S6': Make the document and the scanning module relatively stable and stationary, and use the image sensor of the scanning module to receive a stable image signal from the document;

Step S7': stop the receiving action of the image sensor after receiving the stable image signal for a first predetermined period of time; and

Step S8: end.

It should be noted that steps S4' to S7' can be repeated until all scanning lines are scanned.

In this embodiment, the light source does not need to be a light source that can be turned on or off quickly to achieve stability, so a common cold-cathode tube can be used. In addition, since the image sensor must discard unstable image signals, the image sensor must have an electronic shutter. Through the control of the electronic shutter, the image signal from the document can be discarded or acquired.

In order to meet the needs of various users, the present invention also provides a scanning method for the user to select the desired scanning mode (high quality scanning mode or normal quality scanning mode).

FIG. 5 shows a flowchart of a scanning method according to a third embodiment of the present invention. As shown in Figure 5, the scanning method of the present embodiment includes the following steps:

Step S1: start;

Step S2: receiving a first mode signal or a second mode signal selected by a user for scanning in high quality or normal quality scanning mode;

Step S3: judging whether it is the first mode signal, if yes, skip to step S4, otherwise, skip to step S9;

Steps S4 to S8: the same as the first embodiment, and will not be described in detail here;

Step S9: continuously turn on the light source to illuminate the document;

Step S10: Make the document and the scanning module generate the predetermined relative displacement, and use the image sensor of the scanning module to start receiving a normal image signal from the document;

Step S11: make the file and the scanning module relatively stable and static;

Step S12: Stop the receiving action of the image sensor after receiving the normal image signal for a second predetermined time; and

Step S13: end.

FIG. 6 shows a flowchart of a scanning method according to a fourth embodiment of the present invention. As shown in Figure 6, the scanning method of the present embodiment includes the following steps:

Step S1: start;

Step S2: receiving a first mode signal or a second mode signal selected by a user for scanning in high quality or normal quality scanning mode;

Step S3: judging whether it is the first mode signal, if yes, jump to step S4', otherwise, jump to step S9;

Steps S4' to S8: the same as the second embodiment, no longer described in detail here; and

Steps S9 to S13: the same as the third embodiment, and will not be described in detail here.

Through the scanning method of the present invention, the image sensor does not receive unstable image signals when vibrating relative to the document, so the image quality obtained by scanning is quite high. Although it may be necessary to extend the scan exposure time to achieve optimal scan brightness, it is quite acceptable to slightly increase the scan time to obtain a greatly improved image quality. Or, even if the exposure time is not extended, the image signals received by the image sensor are all stable image signals without unstable image data. Although this will reduce the exposure time, the overall scanning effect will still be more accurate than the unstable image signal received during this period. That is to say, the negative impact of adding the unstable image signal on the image data of the entire scanning line is greater than the impact of removing the unstable signal but reducing the exposure time, so the latter The quality is still higher than the former.

In addition, the present invention also provides a mechanism for the user to select the scanning mode, allowing the user to decide whether to scan in the high-quality or normal-quality scanning mode, so this method can meet the special requirements for scanning speed and scanning quality. user.

The specific embodiments proposed in the detailed description of the preferred embodiments are only used to facilitate the description of the technical content of the present invention, rather than restricting the present invention to the above-mentioned embodiments in a narrow sense, without departing from the spirit of the present invention and the following claims Under the situation of the book, the implementation of various changes all belong to the scope of the present invention.

Symbol Description

S1-S13 Steps of the scanning method

S4’-S7’ steps of scanning method

Claims (10)

1. the scan method that can improve scanning quality is characterized in that, comprises following steps:

(a) drive a file or one scan module, make described file and described scan module produce a predetermined relative displacement;

(b) make described file and described scan module relatively stable static;

(c) open a light source and be used for this document that throws light on, and utilize an image sensor of described scan module to receive a stable image signal from described file; And

(d) receive the reception action that stops described image sensor after described stable image signal continues one period first schedule time, and closing described light source.

2. the scan method that improves scanning quality as claimed in claim 1 is characterized in that, described step (a) comprises:

Driving described file makes it produce described predetermined relative displacement with respect to static described scan module.

3. the scan method that improves scanning quality as claimed in claim 1 is characterized in that, described step (a) comprises:

Driving described scan module makes it produce described predetermined relative displacement with respect to static described file.

4. the scan method that improves scanning quality as claimed in claim 1 is characterized in that, described light source is a light emitting diode.

5. the scan method that improves scanning quality as claimed in claim 1 is characterized in that, more comprises following steps:

Reception is from selected one first mode signal of a user or one second mode signal;

When receiving described first mode signal, carry out described step (a) to (d); And

When receiving described second mode signal, carry out following steps:

(a1) continue to open the described light source described file that is used for throwing light on;

(b1) make described file and described scan module produce described predetermined relative displacement, and utilize the described image sensor of described scan module to begin to receive a common image signal from described file;

(c1) make described file and described scan module relatively stable static; And

(d1) receiving the reception action that stops described image sensor after described common image signal continues one period second schedule time.

6. the scan method that can improve scanning quality is characterized in that, comprises following steps:

(a) continue to open the light source file that is used for throwing light on;

(b) drive a file or one scan module, make described file and described scan module produce a relative displacement of being scheduled to, utilize an image sensor of described scan module to give up a unstable image signal simultaneously from described file;

(c) make described file and described scan module relatively stable static, and utilize the stable image signal of the described image sensor reception of described scan module from described file; And

(d) receiving the reception action that stops described image sensor after described stable image signal continues one period first schedule time.

7. the scan method that improves scanning quality as claimed in claim 6 is characterized in that, described step (b) comprises:

Driving described file makes it produce described predetermined relative displacement with respect to static described scan module.

8. the scan method that improves scanning quality as claimed in claim 6 is characterized in that, wherein said step (b) comprises:

Driving described scan module makes it produce described predetermined relative displacement with respect to static described file.

9. the scan method that improves scanning quality as claimed in claim 6 is characterized in that, described image sensor is the image sensor with an electronic shutter.

10. the scan method that improves scanning quality as claimed in claim 6 is characterized in that, more comprises following steps:

Reception is from selected one first mode signal of a user or one second mode signal;

When receiving described first mode signal, carry out described step (a) to (d); And

When receiving described second mode signal, carry out following steps:

(a1) continue to open the described light source described file that is used for throwing light on;

(b1) make described file and described scan module produce described predetermined relative displacement, and utilize the common image signal of the described image sensor reception of described scan module from described file;

(c1) make described file and described scan module relatively stable static; And

(d1) receiving the reception action that stops described image sensor after described common image signal continues one period second schedule time.

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