LED display apparatus

• US 5,444,456 A
• Filed: 10/21/1993
• Issued: 08/22/1995
• Est. Priority Date: 05/23/1991
• Status: Expired due to Fees

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Ohta, Masuo, Sako, Yukinobu
• Primary Examiner(s): Kuntz, Curtis
• Assistant Examiner(s): HARVEY, MINSUN OH
• Application Number:
  US08/140,623
• Time in Patent Office: 670 Days
• Field of Search: 345/31, 345/39, 345/40
• US Class Current: 345/39
• CPC Class Codes: G09F 9/33 being semiconductor devices, e.g. diodes
• CPC Class Codes: G09G 3/005 forming an image using a quickly moving array of imaging elements, causing the human eye to perceive an image which has a larger resolution than the array, e.g. an image on a cylinder formed by a rotating line of LEDs parallel to the axis of rotation

Abstract

In connection with a display apparatus that is held and swung by an operator to display images of pictures, letters, etc. in space using an afterimage effect, a party situated opposite to the operator is enabled to recognize the images displayed always at the central position of the swing range and with the same dimensions irrespective of the swinging speed and to see the same images displayed even of an asymmetrical pattern irrespective of the directions of the swing of the apparatus. The display apparatus has a transparent protective case covering both side faces, right and left, of an array of LEDs, a measuring unit to measure the cycle time of right and left reciprocating motion, a computing unit to process by computation the measured cycle time, a memory unit to memorize the processed results and a timer circuit unit to control turning the LEDs on and off. This set-up enables a party situated opposite to the operator of the display apparatus to see correct images of letters and pictures displayed always at the center of the swinging width range regardless of the swinging speed.

Claims

1. A hand held LED display apparatus comprising:

a body including a front and a back;

an array of LEDs arranged in line and coupled to the body;

inertial sensor means, situated in said body at one end of the LED array, consisting of a pair of fixed contacts and a moveable contact for generating at least one signal indicating a change in inertia of said apparatus responsive to an inertial force produced when said apparatus is reciprocated from a first direction to a second direction;

memory means for receiving and storing data representing timing for turning on and off each individual LED; and

control means coupled to said memory means, said inertial sensor means and said LEDs for receiving said timing data from said memory means, for receiving said at least one signal from said inertial sensor means and for providing signals to turn on and turn off the LEDs according to the timing data and said at least one signal so that light is displayed and afterimages are caused which are perceived to form an image when said apparatus is moved within a range with reciprocating motion.

2. An LED display apparatus according to claim 1, wherein said protective case includes a plurality of portions forming protective ribs, said protective ribs being situated between respective pairs of LEDs in said LED array.

3. An LED apparatus according to claim 1, wherein:

said range has a right side and a left side,

the apparatus is movable between said right side and said left side,

said inertial sensor means including means for producing a first signal indicating when said apparatus is moved from the extreme right side to said left side and producing a second signal when the apparatus is moved from the extreme left side to said right side, and

said control means

a) for receiving said first and second signals, and

b) for controlling said turn on and turn off signals to turn on and off said LEDs in response to said first signal and said second signal so that said image perceived from said afterimages is in the correct direction.

4. An LED apparatus according to claim 1, further comprising a transparent protective case that covers the LED array, and through which the LEDS emit light in at least two directions including towards the front of said body and toward the back of said body.

5. An LED display apparatus comprising:

a body including a front and a back;

an array of LEDs arranged in line and coupled to the body;

inertial sensor means, situated in said body at one end of the LED array, consisting of a pair of fixed contacts and a moveable contact for generating at least one signal indicating a change in inertia of said apparatus responsive to an inertial force produced when said apparatus is reciprocated from a first direction to a second direction, said sensor having means for measuring a cycle of reciprocating motion of said apparatus;

memory means for receiving and storing a plurality of signals representing timing data corresponding to the turning on and off of individual LEDs;

computing means for computing timing data for turning on and turning off the LEDs and providing said plurality of signals representing said timing data to said memory means; and

a timer circuit having driving on-off timers that turns on and turns off the LEDs according to the plurality of signals corresponding to the timing data in the memory means so that light is displayed and afterimages are caused which are perceived to form an image when said apparatus is moved within a range with reciprocating motion;

wherein said computing means responsive to said at least one signal adjusts said timing data so that the image is displayed at the center of the range reciprocating motion.

6. An LED display apparatus according to claim 5, wherein the computing means computes the timing data for turning on and turning off from the cycle of the reciprocating motion.

7. An LED display apparatus according to claim 5, wherein:

said range has a right side and a left side,

the apparatus is movable between said right side and said left side,

the computing means computes timing for data to display the images starting from said left side when the apparatus is moved from said left side to said right side, and

the computing means computes the timing data to display said image starting from said right side when the apparatus is moved from said right side to said left side.

8. An LED apparatus according to claim 5, further comprising a transparent case that protects the LED array, and through which light is emitted in at least two directions including towards the front of said body and towards the back of said body.

9. An LED apparatus, comprising:

a body;

an array of LEDs coupled to the body and emitting light in at least two directions;

inertial sensor means, situated in said body at one end of the LED array, consisting of a pair of fixed contacts and a moveable contact for generating at least one signal indicating a change in inertia of said apparatus responsive to an inertial force produced when said apparatus is reciprocated from a first direction to a second direction, said sensor having means for measuring a direction of motion of said body;

computing means

a) for receiving said at least one signal from said sensor, and

b) for computing timing data based on said at least one signal for turning on and turning off each LED of said array as a function of frequency of said body movement based upon said at least one signal,

memory means for receiving and storing said timing data corresponding to the turning on and off of each LED of said array; and

timing means, for turning on and turning off each LED of said array according to the timing data in the memory means.

10. An LED apparatus according to claim 9, wherein said LEDs are arranged in line.

11. An LED apparatus according to claim 9, wherein said array of LEDs emit light in at least two directions.