Image display apparatus

• US 5,583,538 A
• Filed: 05/22/1995
• Issued: 12/10/1996
• Est. Priority Date: 09/19/1984
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Watanabe, Yasuhiro, Tanaka, Kensaku
• Primary Examiner(s): SARAS, STEVEN J
• Application Number:
  US08/445,552
• Time in Patent Office: 568 Days
• Field of Search: 345/131, 345/121, 345/145, 345/157, 345/163, 345/156, 178/18
• US Class Current: 345/684
• CPC Class Codes: G09G 5/346 for systems having a bit-mapped display memory

Abstract

An image display apparatus has a display memory for storing a one-frame image, a mouse for pointing a desired point on a CRT display, a keyboard including a key for instructing display area displacement, and an MPU to control display area displacement in response to operation of the key by the operator. The cursor can be displaced to a desired point on the screen to aid efficient panning without frequent shifting of the display area.

Claims

1. An image display apparatus comprising:

memory means for storing image data;

display means for displaying part of the image data in said memory means;

a pointing device moved along a given plane so as to designate a displacement amount of the display of said part of the image data in said memory means which can be displayed on said display means while the displayed part moves;

ratio setting means for manually setting a ratio of displacement amount of said pointing device to the displacement amount of the display of said part of the image data of said memory means; and

calculating means for calculating the displacement amount of said memory means in accordance with the ratio set by said ratio setting means and an instruction of said pointing device.

2. An apparatus according to claim 1, wherein said memory means comprises a random access memory.

3. An apparatus according to claim 1, wherein said display means comprises a cathode-ray tube.

4. An image displaying method comprising the steps of:

displaying part of image data stored in memory means;

moving a cursor along a given plane so as to designate a displacement amount of the display of the part of the image data in the memory means which can be displayed in said displaying step while the displayed part moves, the cursor being moved by a pointing device;

manually setting a ratio of displacement of the pointing device to the displacement amount of the display of the part of the image data of the memory means; and

calculating the displacement amount of the memory means in accordance with the ratio set in said manually setting step and an instruction of the pointing device.