Chi Chung Chung

US Patent:

48736805, Oct 10, 1989

Filed:

Mar 13, 1987

Appl. No.:

7/025394

Inventors:

Chi H. Chung - San Jose CA
Theodore D. Rees - Mountain View CA
Ian Turner - Sunnyvale CA

Assignee:

Laserdrive Ltd. - Santa Clara CA

International Classification:

G11B 7007

US Classification:

369 59

Abstract:

A system for storing and retrieving encoded data on an optical recording medium using pit edge detection is disclosed. The pit extension characteristics of a given medium are determined by first using laser beam test write pulses to form one or more pits on the medium and then detecting the time durational difference between the pulse width of the test write pulses and the duration of the leading edge transitions to trailing edge transitions of the corresponding pits formed on said medium. This difference value may be stored in a certification sector of the medium. Subsequent write pulses are modified in duration in an amount equal to this detected durational difference. For forming a pit that is longer than a predetermined minimum length, the corresponding write pulse is made non-continuous in order to minimize cumulative pit extension. The number of non-continuous pulses used to form a given pit is a function of the desired length, the on time of each pulse and the duration of the off time between adjacent write pulses, said off time being a predetermined length to cause pit extension overlap between the portions of the pit formed during the one time of each said write pulse, thereby forming a continuous pit.

US Patent:

44563361, Jun 26, 1984

Filed:

Oct 5, 1982

Appl. No.:

6/433026

Inventors:

Chi H. Chung - San Jose CA
Sun Lu - San Jose CA
David B. Chung - Alhambra CA

Assignee:

Minnesota Mining and Manufacturing Company - St. Paul MN

International Classification:

G02F 113

US Classification:

350338

Abstract:

A reflector for use in liquid crystal displays is disclosed comprising a plate having a micro-lenticular surface over which are successive layers of reflective material, such as aluminum or silver and a light transparent material having a low index of refraction, i. e. , an inex of refraction below that of SiO. sub. 2, which is in optical contact with the reflective layer. The present invention also contemplates the method of fabricating such a reflective surface.

US Patent:

45518289, Nov 5, 1985

Filed:

Mar 18, 1983

Appl. No.:

6/476503

Inventors:

Chi H. Chung - San Jose CA

Assignee:

Minnesota Mining and Manufacturing Company - St. Paul MN

International Classification:

G11B 700

US Classification:

369275

Abstract:

Quadrilayer optical DRAW medium which differs from prior trilayer optical DRAW media by having a thin triggering layer adjacent each of the optical spacer and light-absorbing layers. The triggering layer is a material, preferably organic, which when heated by a modulated laser-diode beam to a temperature less than the melting point of the optical spacer layer develops substantial vapor pressure or otherwise rapidly expands to implement or enhance the formation of pits or bubbles in the light-absorbing layer without disturbing the optical spacer layer or its function of protecting the substrate of the medium.

US Patent:

50560794, Oct 8, 1991

Filed:

Aug 4, 1988

Appl. No.:

7/228395

Inventors:

Chi H. Chung - San Jose CA

Assignee:

Literal Corporation - Colorado Springs CO

International Classification:

G11B 700

US Classification:

369100

Abstract:

A method and apparatus for increasing the information storage capacity of optical recording structures by utilizing a laser beam of different powers to produce a selected one of a plurality of different physical states. These states each produce a different optical contrast. If the number of different optical contrasts is greater than two, then encoding schemes based on three or more bits may be used to store the information thus increasing the data density on the optical recording structure, such as an optical disc. In order to promote the stability of the physical states and to enhance the speed of transition between the states, a stabiliment layer is added adjacent and covering the photosensitive layer of the disc. The stabiliment layer itself is ablated in the ablation state of the photosensitive layer.

US Patent:

57726094, Jun 30, 1998

Filed:

Jun 28, 1996

Appl. No.:

8/672637

Inventors:

Kim Nguyen - San Jose CA
Chi J. Chung - Sunnyvale CA
Thomas J. Palermo - San Jose CA

Assignee:

Target Therapeutics, Inc. - Fremont CA

International Classification:

A61B 500

US Classification:

600585

Abstract:

This invention is a guidewire for guiding a catheter and is used for accessing a targeted site within a lumen system in a body. The guidewire or guidewire section has a wire core, a distal tip region, a polymeric tie layer, and a lubricious coating. The tie layer is preferably constructed to provide for sections of varying flexibility along the length of the guidewire. Variations of the tie layer provide for axially spaced sections of varying flexibility, radially layers of varying flexibility of both. In a special variation, the tie layer is constructed with at least one section providing increased stiffness distally.