TWI519124B - Scanning device and method - Google Patents

Description

Scanning device and method

The invention relates to a scanning device and a method, in particular to a scanning device and a method for obtaining images of two or more different exposure times by using one scanning process.

The popularity of scanning technology has enabled many images and manuscripts to be stored in a digital manner. However, in the image draft, different regions have different optical densities, and the dark areas of the draft and the bright areas of the draft cannot simultaneously obtain good digital images with the same scanning parameters.

For example, in order to obtain good image detail in the dark area, a longer exposure time must be set so that the image sensor can fully sense the dark area light, and for the bright area, an overexposed bright white image may be obtained; Conversely, in order to obtain a clear bright area image, a shorter exposure time must be set so that the image sensor does not overly sense the bright area light, while for dark areas, it may appear dark. In order to obtain a good quality image, a high dynamic range scanning technology has been developed, which uses multiple scans to obtain digital images of different exposure parameters, and then performs image processing such as overlaying, etc., to obtain both bright and dark areas. Clear image. However, this method requires multiple scans. When the sensor obtains the first exposure image, it needs to return to the initial position and return to zero correction for the next scan to obtain the second exposure image, which is quite a waste of time; The re-execution of the scanning process may cause a problem of image alignment offset.

In view of this, how to obtain scanned images efficiently and accurately is an urgent task.

The present invention provides a scanning device and method for sensing an object object by a first exposure time and a second exposure time in a scanning direction sequentially at each scanning position of the object. The light of the object is transmitted or transmitted to form a first image and a second image. In this way, two or more images of different exposure times can be obtained by one scanning process.

The scanning device according to an embodiment of the invention comprises a light source, an image sensor and a driving module. The light source is configured to generate a light to illuminate an object; the image sensor is configured to sense, according to a scanning direction, the light reflected or transmitted through the object by a first exposure time and a second exposure time in each scanning position of the object. The driving module is configured to drive the image sensor and the object to move relative to each other, so that the image sensor scans the object.

A scanning method according to another embodiment of the present invention includes providing a light source for generating a light to illuminate an object; and driving a image sensor with a driving module and moving the objects relative to each other to cause the image sensor to scan along a scan The direction sequentially senses the light reflected or transmitted through the object by a first exposure time and a second exposure time at each scanning position of the object to form a first image and a second image.

The purpose, technical contents, features, and effects achieved by the present invention will become more apparent from the detailed description of the appended claims.

Referring to FIG. 1 , a scanning device 1 according to an embodiment of the present invention includes a light source 2 , an image sensor 3 , and a driving module 4 . The light source 2 is used to generate a light to illuminate an object. For example, the light source 2 can be a light emitting diode or a cold cathode fluorescent lamp (CCFL). The image sensor 3 is configured to sense the light reflected or transmitted through the object by a first exposure time and a second exposure time in a scanning direction sequentially to form a first image and a second image. In one embodiment, the image sensor 3 can be a charge coupled device (CCD), a complementary metal oxide semiconductor (CMOS) sensor, or a contact image sensor (CIS). Preferably, the scanning device 1 further includes an optical lens 5 disposed on the light incident side of the image sensor 3 for concentrating light reflected or transmitted through the object to the image sensor, wherein the optical lens 5 can be a rod lens (rod lens). The driving module 4 is configured to drive the image sensor 3 and the objects to move relative to each other, so that the image sensor 3 scans the object. For example, the drive module 4 can include a stepper motor to drive the sensor 3 relative to the object.

In one embodiment, the scanning device 1 further includes a user interface 6 electrically connected to the image sensor 3. The user can set the first exposure time and the second exposure time through the user interface 6, or set the scanning resolution to obtain the first image and the second image with different resolutions. For example, the user interface 6 can be a button module, a touch module or even a voice control module, which is located on the body of the scanning device 1 or extends outside; or through a computer software to set scanning parameters.

In the above, the scanning device 1 further includes an image processing module 7 electrically connected to the image sensor 3 for performing image processing on the first image and the second image. After the image sensor 3 obtains the first image and the second image, it is transmitted to the image processing module 7. The image processing module 7 can adjust image properties, overlays, image segmentation and merging, etc. according to user requirements. It can be understood that the image processing module includes a software body, a firmware, or a combination thereof.

For example, in an embodiment, when the user wants to scan an object, according to the optical density of the object, the first exposure time is 1 ms and the second exposure time is 10 ms through the user interface 6 of the scanning device 1. . 3 is a schematic diagram of a scanning path according to an embodiment of the present invention. As shown in FIG. 3, when the scanning device 1 starts scanning, the image sensor 3 moves from the initial position P ₀ along the scanning direction D, and sequentially passes through a first The scan line L ₁ , a second scan line L ₂ ... and so on, will not return to the initial position P ₀ until the entire scan area A is passed. Based on the exposure time set by the user, when the image sensor 3 through the first scan line L _1, a first exposure time of residence will first 1ms, to obtain a first image of a first scan line L _1, and then a second visit 10ms exposure time, to obtain a second image of the first scan line L of _1, a first scan line of the scan time for a first exposure time second exposure time 1ms and 10ms 11ms total sum, then, the image sensor 3 will Moving to the second scan line L ₂ , the subsequent process is followed by the same. In an embodiment, the image sensor 3 can also output data and continue exposure when the exposure time reaches the first exposure time of 1 ms, and output data again when the second exposure time reaches 10 ms, thereby shortening the scanning. time.

In the embodiment, the image sensor module 3 includes a computer. After the image sensor 3 obtains the complete first image and the second image of the object, the image sensor module 3 transmits the image to the image processing module 7. In one embodiment, the image processing module 7 includes a computer. The software is installed on a computer, and the computer is electrically connected to the scanning device 1. With the aid of the computer software, the user can process the first image and the second image, for example, a high exposure time image and a low exposure time image overlay to obtain a high dynamic range image. It can be understood that the image processing module 7 can also be directly located on the scanning device 1 to facilitate the user's immediate operation.

Please refer to FIG. 1, FIG. 2 and FIG. 3 simultaneously, which illustrate a scanning method according to an embodiment of the present invention. First, a light source 2 is provided for generating a light to illuminate an object (S1); an image sensor 3 is driven by a driving module 4 and the objects are moved relative to each other to cause the image sensor 3 to follow a scanning direction D. The light reflected or transmitted through the object is sensed by a first exposure time and a second exposure time at each scanning position of the object (S2) to form a first image and a second image. Therefore, after obtaining the first image, the image sensor 3 does not need to return to the initial position P _{0 to} zero correction, and can be re-sensed at the same position to obtain the second image. Finally, an image processing (S3) is performed on the first image and the second image. For example, through an image processing module 7, the user can perform image quality on the high exposure time image and the low exposure time image of the same object. Adjust, overlay, split or merge, but not limited to get a good image.

In one embodiment, the user can set the first exposure time and the second exposure time through the user interface 6. The user interface 6 can be a button module, a touch module or even a voice control module. The body of the scanning device 1 is extended to the outside; or through a computer software to set the scanning parameters. The detailed description of the above steps is as described above and will not be further described herein. Preferably, in an embodiment, the user can set the desired output resolution according to different exposure times, so the resolutions of the first image and the second image may be different.

In summary, the scanning apparatus and method of the present invention provide a sensor that senses object reflection or a first exposure time and a second exposure time in a scanning direction sequentially at each scanning position of the object. The light of the object is transmitted to form a first image and a second image. In this way, two or more different exposure times can be obtained by one scanning process. The image, and then the image processing, can simultaneously obtain a clear image of both the dark area and the bright area. In addition to saving scan time, the problem of image alignment offset is also avoided.

The embodiments described above are only intended to illustrate the technical idea and the features of the present invention, and the purpose of the present invention is to enable those skilled in the art to understand the contents of the present invention and to implement the present invention. That is, the equivalent variations or modifications made by the spirit of the present invention should still be included in the scope of the present invention.

1‧‧‧ scanning device

2‧‧‧Light source

3‧‧‧Image sensor

4‧‧‧Drive Module

5‧‧‧ lens

6‧‧‧User interface

7‧‧‧Image Processing Module

A‧‧‧Scanning area

D‧‧‧Scanning direction

L ₁ ‧‧‧first scan line

L ₂ ‧‧‧second scan line

S1~S3‧‧‧ scanning method

P ₀ ‧‧‧ initial position

1 is a schematic diagram of a scanning device according to an embodiment of the present invention.

2 is a flow chart of a scanning method according to another embodiment of the present invention.

FIG. 3 is a schematic diagram of a scan path according to an embodiment of the present invention.

1‧‧‧ scanning device

2‧‧‧Light source

3‧‧‧Image sensor

4‧‧‧Drive Module

5‧‧‧ lens

6‧‧‧User interface

7‧‧‧Image Processing Module

Claims (19)

A scanning device includes: a light source for generating a light to illuminate an object; and an image sensor for sequentially sliding a scanning time to each scanning position of the object for a first exposure time and a The second exposure time senses the light reflected or transmitted through the object to form a first image and a second image; and a driving module for driving the image sensor and the object are opposite to each other Move to cause the image sensor to scan the object. The scanning device of claim 1, wherein the light source comprises a light emitting diode or a cold cathode fluorescent lamp (CCFL). The scanning device of claim 1, further comprising: an optical lens disposed on the light incident side of the image sensor for collecting the light reflected or transmitted through the object to the image sensor . The scanning device of claim 3, wherein the optical lens comprises a rod lens. The scanning device of claim 1, further comprising: an image processing module electrically connected to the image sensor for performing image processing on the first image and the second image. The scanning device of claim 1, further comprising: a user interface electrically connected to the image sensor, wherein the user sets the first exposure time and the second exposure time through the user interface. The scanning device of claim 1, wherein the driving module comprises a stepping motor. The scanning device of claim 1, wherein the image sensor comprises a charge coupled device (CCD), a complementary metal oxide semiconductor (CMOS) sensor, or a contact image sensor (CIS). The scanning device of claim 1, wherein the first image and the second image are parsed Different degrees. A scanning method includes: providing a light source for generating a light to illuminate an object; and driving an image sensor with a driving module and moving the object relative to each other to cause the image sensor to follow a scanning direction The light reflected or transmitted through the object is sensed by a first exposure time and a second exposure time at each scanning position of the object to form a first image and a second image. The scanning method of claim 10, wherein the light source comprises a light emitting diode or a cold cathode fluorescent lamp (CCFL). The scanning method of claim 10, further comprising concentrating, by the optical lens, the light reflected or transmitted through the object to the image sensor. The scanning method of claim 12, wherein the optical lens comprises a rod lens. The scanning method of claim 10, further comprising: performing image processing on the first image and the second image. The scanning method of claim 14, wherein the image processing comprises adjusting image properties, overlays, segments, and merges. The scanning method of claim 10, further comprising setting the first exposure time and the second exposure time through a user interface. The scanning method of claim 10, wherein the driving module comprises a stepping motor. The scanning method of claim 10, wherein the image sensor comprises a charge coupled device (CCD), a complementary metal oxide semiconductor (CMOS) sensor, or a contact image sensor (CIS). The scanning method of claim 10, wherein the first image and the second image have different resolutions.