Dense LED matrix for high resolution full color video

• US 4,857,801 A
• Filed: 05/28/1987
• Issued: 08/15/1989
• Est. Priority Date: 04/18/1983
• Status: Expired due to Term

• Current Assignee: Litton Systems Incorporated
• Original Assignee: L3 Technologies ESS, Inc. (L3Harris Technologies, Inc.)
• Inventors: Farrell, James F.
• Primary Examiner(s): WIEDER, KENNETH A
• Application Number:
  US07/056,360
• Time in Patent Office: 810 Days
• Field of Search: 313/498, 313/499, 313/500, 357/17, 357/19, 357/32, 357/45, 357/55, 250/552, 250/553, 437/180, 437/204, 437/205, 437/906, 437/915
• US Class Current: 313/500
• CPC Class Codes: G09F 9/33 being semiconductor devices, e.g. diodes
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Abstract

A display for full color video includes light emitting diodes (LED'"'"'s) arranged to increase LED density and thereby achieve enhanced resolution. The matrix is of the type that includes a plurality of physically separate, addressable dice fixed to a substrate. The display of the invention achieves increased density by utilizing dice of at least two distinct predetermined heights which are positioned onto the substrate in a predetermined pattern whereby the heights of adjacent dice differ. In this way, the closeness of inter-die spacing is not limited by the size of a positioning tool for grasping dice adjacent their upper portions.

Claims

1. In a LED matrix of the type that includes a plurality of physically separate, addressable dice fixed to a substrate, the improvement comprising, in combination:

(a) individual LED dice being of at least two distinct predetermined heights; and

b) said dice being of such heights and positioned onto said substrate in a predetermined pattern whereby the heights of adjacent dice differ so that the closeness of inter-die spacing is not limited by the size of a positioning tool for grasping dice adjacent the upper portions thereof.

2. A LED matrix as defined in claim 1 wherein the spacing between adjacent dice is less than 0.005 inch.

3. A LED matrix as defined in claim 1 further characterized in that:

(a) each of said dice is individually addressable; and

(b) said dice are in electrical contact with said substrate so that said dice may be addressed by means of said substrate.

4. A LED matrix as defined in claim 3 including red, blue and green emitting dice.

5. A LED matrix as defined in claim 4 wherein dice of the same emission spectrum are of equal heights.

6. A LED matrix as defined in claim 5 wherein three of said dice are arranged into a pixel including each of said emission spectra.

7. A LED matrix as defined in claim 5 wherein four of said dice are arranged into a pixel including each of said emission spectra.

8. A LED matrix as defined in claim 3 wherein said dice are fixed to said substrate by a cement.

9. A LED matrix as defined in claim 3 wherein said dice are fixed to said substrate by a solder.

10. A LED matrix as defined in claim 3 wherein said dice are fixed to said substrate by a eutectic.