Cursor for LCD displays

• US 5,214,414 A
• Filed: 04/12/1991
• Issued: 05/25/1993
• Est. Priority Date: 04/12/1991
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Russell, Gregory F., Levine, James L.
• Primary Examiner(s): Weldon, Ulysses
• Application Number:
  US07/685,322
• Time in Patent Office: 774 Days
• Field of Search: 340/709, 340/710, 340/711, 340/706, 340/724
• US Class Current: 345/157
• CPC Class Codes: G06F 2203/04801 Cursor retrieval aid, i.e. visual aspect modification, blinking, colour changes, enlargement or other visual cues, for helping user do find the cursor in graphical user interfaces
• CPC Class Codes: G06F 3/04812 Interaction techniques based on cursor appearance or behaviour, e.g. being affected by the presence of displayed objects
• CPC Class Codes: G09G 3/3611 Control of matrices with row and column drivers
• CPC Class Codes: G09G 5/08 Cursor circuits

Abstract

A method displays a visual "trail" (12b) behind a moving cursor (12a) so that the cursor does not disappear from a liquid crystal display (12) during rapid cursor movement. The method interpolates and displays one or more intermediate cursor locations between a previous cursor location and a present cursor location. A method also extrapolates one or more future cursor locations (12c) from a present location and prematurely turns on, or biases, pixels located at the extrapolated future locations so that a significantly shorter period of time is required to cause the pixels to become visually distinct. The method also interpolates intermediate cursor locations between the present location and the one or more extrapolated locations and prematurely turns on the pixels at the interpolated locations.

Claims

1. A method for operating a display device that is coupled during use to a data processor, comprising the steps of:

receiving an input signal that directs a movement of a displayed image object from a first location to a second location;

displaying the image object at the second location;

determining if a directed rate of movement of the image object between the first location and the second location is less than a predetermined maximum rate of movement;

if it is determined that the directed rate of movement of the image object between the first location and the second location is less than the predetermined maximum rate of movement, the method includes a step of terminating the display of the image object at the first location;

else, if it is determined that the rate of movement of the image object between the first location and the second location is not less than the predetermined maximum rate of movement, the method includes the further steps of,

displaying a representation of the image object at one or more intermediate locations between the first location and the second location for visually indicating a direction of movement of the image object between the first location and the second location;

determining if one or more of the representations of the displayed image object, and also the image object that is displayed at the first location, have been displayed for a period of time that is equal to or greater than a predetermined maximum period of time; and

if so, terminating the display of the image object that is displayed at the first location, and any representations thereof, that are determined to have been displayed for a period of time equal to or greater than the predetermined maximum period of time.

2. A method as set forth in claim 1 wherein the step of displaying the image object at the second location and the step of displaying the representation of the image object at one or more intermediate locations each include a step of energizing a plurality of display device pixels, and wherein the predetermined maximum period of time has a value that is a function of an amount of time required for the display device pixels to become visually apparent after being energized.

3. A method as set forth in claim 1 wherein the step of displaying the image object at the second location includes a step of energizing a plurality of display device pixels, and wherein the predetermined maximum rate of movement has a value that is a function of an amount of time required for the display device pixels to become visually apparent after being energized.

4. A method as set forth in claim 1 wherein the step of displaying a representation of the image object includes a step of displaying a simplified image object.

5. A method of operating a display device that is coupled during use to a data processor, comprising the steps of:

receiving an input signal that directs a movement of a displayed image object from a first location to a second location;

displaying the image object at the second location;

determining if a directed rate of movement of the image object between the first location and the second location is less than a predetermined maximum rate of movement;

if it is determined that the directed rate of movement of the image object between the first location and the second location is less than the predetermined maximum rate of movement, the method includes a step of terminating the display of the image object at the first location;

else, if it is determined that the rate of movement of the image object between the first location and the second location is not less than the predetermined maximum rate of movement, the method includes the further steps of,

initiating a display of the image object at least one probable future location of the image object, the at least one probable future location being selected as a function of a previous location of the image object and also as a function of a previous directed rate of motion of the image object; and

in response to a subsequent determination that a selected probable future location where the display of the image object has been initiated is not a correct location, terminating the display of the image object at the incorrect location before the image object becomes visually apparent.

6. A method as set forth in claim 5 wherein the step of initiating the display of the image object includes a step of energizing a plurality of display device pixels, and wherein the at lest one probable future location is selected also as a function of an amount of time required for the display device pixels to become visually apparent after being energized.

7. A method as set forth in claim 5 wherein the step of displaying the image object at the second location includes a step of energizing a plurality of display device pixels, and wherein the predetermined maximum rate of movement has a value that is a function of an amount of time required for the display device pixels to become visually apparent after being energized.

8. A method as set forth in claim 5 wherein the step of initiating the display of the image object includes the further step of:

initiating the display of a representation of the image object at one or more intermediate locations between the second location and the at least one selected probable future location of the image object.

9. A method as set forth in claim 5 wherein the step of initiating the display of the image object includes the further step of:

displaying a representation of the image object at one or more intermediate locations between the first location and the second location for visually indicating a direction of movement of the image object between the first location and the second location.

10. Apparatus for controlling the operation of a liquid crystal display device, comprising:

a liquid crystal display device having a plurality of pixels;

control means coupled to the liquid crystal display device for controlling the energizing and de-energizing of said plurality of pixels so as to display an image object; and

pointing means having an output coupled to said control means for providing a signal to said control means for specifying a direction of movement and a rate of movement of the displayed image object from a first location to a second location;

wherein

said control means is responsive to the signal for, displaying the image object at the second location;

for determining if a specified rate of movement of the image object between the first location and the second location is less than a predetermined maximum rate of movement; and

in response to a determination by said control means that the specified rate of movement of the image object between the first location and the second location is not less than the predetermined maximum rate of movement,

for displaying a representation of the image object at one or more intermediate locations between the first location and the second location for visually indicating a direction of movement of the image object between the first location and the second location;

for determining if one or more of the representations of the displayed image object, and also the image object that is displayed at the first location, have been displayed for a period of time that is equal to or greater than a predetermined maximum period of time; and

if so, for terminating the display of th image object that is displayed at the first location, and any representations thereof, that are determined to have been displayed for a period of time equal to or greater than the predetermined maximum period of time.

11. Apparatus as set forth in claim 10 wherein the predetermined maximum period of time and also the predetermined maximum rate of movement each have a value that is a function of an amount of time required for the pixels to become visually apparent after being energized.

12. Apparatus for controlling the operation of a liquid crystal display device, comprising:

a liquid crystal display device having a plurality of pixels;

control mean coupled to the liquid crystal display device for controlling the energizing and de-energizing of said plurality of pixels so as to display an image object; and

pointing means having an output coupled to said control means for providing a signal to said control means for specifying a direction of movement and a rate of movement of the displayed image object from a first location to a second location;

wherein

said control means is responsive to the signal for,

displaying the image object at the second location;

for determining if a specified rate of movement of the image object between the first location and the second location is less than a predetermined maximum rate of movement; and

in response to a determination by said control means that the specified rate of movement of the image object between the first location and the second location is not less than the predetermined maximum rate of movement,

for initiating a display of the image object at least one probable future location of the image object, the at least one probable future location being selected as a function of a previous location of the image object and as a function of a previous specified rate of motion of the image object; and

in response to a subsequent determination by said control means that a probable future location where the display of the image object has been initiated is not a correct location, for terminating the display of the image object at the incorrect location before the image object becomes visually apparent.

13. Apparatus as set forth in claim 12 wherein the at least one probable future location is selected also as a function of an amount of time required for the pixels to become visually apparent after being energized.