This Application claims priority of Taiwan Patent Application No. 100108049, filed on Mar. 10, 2011, the entirety of which is incorporated by reference herein.
1. Field of the Invention
The present invention is related to an integrated contact image sensor module (CISM), and more particularly to an integrated CISM that captures an image according to a motion signal and then transmits data with a universal transmission interface.
2. Description of the Related Art
Image scanners are commonly used in offices or homes for scanning. For example, a user can use an image scanner to scan documents, photographs or films, so as to print or store the scanned image.
When an image scanner is operated, an image sensing module such as a charge couple device (CCD) or contact image sensor (CIS), is employed to generate electronic signals of images. Since the contact image sensor has less volume than the charge couple device, the contact image sensors are usually applied to scanners, multi-function business machines or photocopiers.
A contact image sensor normally shines light on an object to be scanned and focuses the reflected light by a lens group on a CCD or a complimentary metal-oxide semiconductor (CMOS) light sensor, and then converts the received optical signals to electronic signals for generating pixel data. Therefore, by moving the contact image sensor to perform scanning, the objects (e.g. documents, photographs or films) are recorded on, output to or transmitted to other electronic devices. However, in a typical contact image sensor module (CISM), it has no relationship between motion information of the contact image sensor and operations of the sensor module. Therefore, in order to complete basic scanning, a user needs to know all of the operations of the CISM, to understand the mutual relationships between the modules within the CISM.
An integrated contact image sensor module (CISM) and an image scanning system are provided. An embodiment of a CISM comprises a light switch circuit, a contact image sensor, an analog to digital converter coupled to the contact image sensor and a controller coupled to the light switch circuit. The light switch circuit turns on a light source according to a light control signal. The contact image sensor captures an image when the light source is turned on and generates an analog signal corresponding to the image. The analog to digital converter converts the analog signal into scan data. The controller provides the light control signal to the light switch circuit according to a motion signal and provides a clock signal to the analog to digital converter, so as to convert the analog signal into the scan data. The controller further provides an interface signal corresponding to the scan data, to an interface module according to the motion signal, and the interface signal conforms to a specific transmission protocol.
Furthermore, an embodiment of an image scanning system is provided. The image scanning system comprises an interface module and an integrated contact image sensor module (CISM). The CISM comprises a light switch circuit, a contact image sensor, an analog to digital converter coupled to the contact image sensor and a controller coupled to the light switch circuit. The light switch circuit turns on a light source according to a light control signal. The contact image sensor captures an image when the light source is turned on and generates an analog signal corresponding to the image. The analog to digital converter converts the analog signal into scan data. The controller provides the light control signal to the light switch circuit according to a motion signal and provides a clock signal to the analog to digital converter, so as to convert the analog signal into the scan data. The controller further provides an interface signal corresponding to the scan data, to the interface module according to the motion signal, and the interface signal conforms to a specific transmission protocol.
A detailed description is given in the following embodiments with reference to the accompanying drawings.
The invention can be more fully understood by reading the subsequent detailed description and examples with references made to the accompanying drawings, wherein:
The following description is of the best-contemplated mode of carrying out the invention. This description is made for the purpose of illustrating the general principles of the invention and should not be taken in a limiting sense. The scope of the invention is best determined by reference to the appended claims.
Moreover, the controller 128 further provides a clock signal clk and a control signal Sctrl2 to the ADC 122 when the motion signal Sstep indicates that the image scanning system 100 has been moved. Thus, the ADC 122 converts the analog signal Vout into a digital scan data Dout, and than transmits the scan data Dout to the interface module 110. Simultaneously, the controller 128 also provides the interface signals PCLK, HREF and VSYNC to the interface module 110 when the motion signal Sstep indicates that the image scanning system 100 has been moved, wherein the interface signals PCLK, HREF and VSYNC are synchronization (sync) signals that conform to a transmission protocol of a subminiature photograph module, for example, the signal PCLK is a pixel sync clock signal, the signal HREF is a horizontal sync signal and the VSYNC is a vertical sync signal. Therefore, a processing unit 112 of the interface module 110 can read the scan data Dout according to the interface signals PCLK, HREF and VSYNC, to obtain the scanned image. For example, the processing unit 112 may be a digital still camera (DSC) chip, thus the interface module 110 and the integrated CISM 120 have the same interface standards, such that the DSC chip directly reads the signals provided by the integrated CISM 120 without additional processes. Furthermore, the processing unit 112 may be a transmission integrated chip (IC) that conforms to universal serial bus (USB) specifications, so that the transmission IC can easily transmit the image data to a backend system (e.g. PC) for storage or use.
As described above, the integrated CISM of the invention appropriately and sequentially turns on a light source and changes the light colors according to the motion information of the image scanning system, to perform object scanning. In addition, the integrated CISM also provides the signals that conform to a transmission protocol of a subminiature photograph module, thereby the integrated CISM can use the interface module to transmit image data to a backend image processing module. Therefore, after receiving the image data, only basic processes and arrangements need to be performed by the backend image processing module to completely obtain a scanned image, thus significantly reducing complexity for users.
While the invention has been described by way of example and in terms of the preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. To the contrary, it is intended to cover various modifications and similar arrangements (as would be apparent to those skilled in the art). Therefore, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements.
Number | Date | Country | Kind |
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100108049 | Mar 2011 | TW | national |