Method of removing memory of scanning apparatus

• US 20040085597A1
• Filed: 11/04/2002
• Published: 05/06/2004
• Est. Priority Date: 11/04/2002
• Status: Active Grant

• Current Assignee: Intellectual Ventures I LLC (Intellectual Ventures LLC)
• Original Assignee: Transpacific IP Group Limited
• Inventors: Lee, Chen-Ho
• Granted Patent: US 7,460,257 B2
• Time in Patent Office: Days
• US Class Current: 358/524
• CPC Class Codes: H04N 1/04 Scanning arrangements , i.e. arrangements for the displacement of active reading or reproducing elements relative to the original or reproducing medium, or vice versaH04N1/387 takes precedence
• CPC Class Codes: H04N 2201/02439 Positioning method
• CPC Class Codes: H04N 2201/03112 Light source
• CPC Class Codes: H04N 2201/04767 by controlling the timing of the signals, e.g. by controlling the frequency o phase of the pixel clock
• CPC Class Codes: H04N 2201/04794 Varying the control or compensation during the scan, e.g. using continuous feedback or from line to line

Abstract

A method of removing memory of a scanning apparatus. The period of a shift signal is adjusted according to the speed of reading data from a scan line by a computer instead of using a memory buffer. Therefore, correct data transmission between the image extraction device and the computer can be achieved. As a result, the cost of the scanning apparatus is reduced.

Claims

1. A method of removing a memory of a scanning apparatus, wherein the scanning apparatus comprises an image extraction device operative to transmit each pixel of data of a scan line to a computer during a period referred to as an exposure time of a dumping signal via a shift signal, the method includes:

adjusting a period of the shift signal according to a speed of reading the data of the scan line by the computer, allowing the computer to finish reading the data of the scan line in the exposure time.

2. The method according to claim 1, wherein when the shift signal transmits each pixel of the data of the scan line to the computer in a time shorter than the exposure time, a waiting time is added to equal the exposure time.

3. The method according to claim 1, wherein the exposure time is constant.

4. The method according to claim 1, wherein the exposure time is variable.

5. The method according to claim 1, wherein the dumping signal is enabled at a high level.

6. The method according to claim 1, wherein the shift signal is enabled at a high level.

7. The method according to claim 1, wherein the image extraction device includes a charge-coupled device.

8. The method according to claim 1, wherein the memory includes a dynamic random access memory.

9. A method of removing a memory from a scanning apparatus, wherein the scanning apparatus includes an image extraction apparatus operative to transmit each pixel of data of a scan line to a computer via a shift signal during a period of a dumping signal, also referred to as an exposure time, the method comprising:

shortening a period of the shift signal when the computer uses a fast processing speed to process the data of the scan line; and

increasing the period of the shift signal when the computer uses a slow processing speed to process the data of the scan line;

wherein the computer has to finish reading the data of the scan line in the exposure time.

10. The method according to claim 9, wherein when each pixel of the data of the scan line is transmitted to the computer in a time shorter than the exposure time, a waiting time is added to equal the exposure time.

11. The method according to claim 9, wherein the exposure time is constant.

12. The method according to claim 9, wherein the exposure time is variable.

13. The method according to claim 9, wherein the dumping signal is enabled at a high level.

14. The method according to claim 9, wherein the shift signal is enabled at a high level.

15. The method according to claim 9, wherein the image extraction device includes a charge-coupled device.

16. The method according to claim 9, wherein the memory includes a dynamic random access memory.