Method for curing light-curable materials

• US 7,066,732 B2
• Filed: 02/11/2002
• Issued: 06/27/2006
• Est. Priority Date: 09/24/1999
• Status: Expired due to Term

• Current Assignee: CAO Group, Inc.
• Original Assignee: CAO Group, Inc.
• Inventors: Cao, Densen
• Primary Examiner(s): Lewis, Ralph A.
• Application Number:
  US10/073,823
• Publication Number:
  US 20020177096A1
• Time in Patent Office: 1,597 Days
• Field of Search: 433/29, 433/215, 606/1, 606/13, 606/16, 607/88, 362/119, 362/800, 362/804
• US Class Current: 433/29
• CPC Class Codes: A61C 19/004 Hand-held apparatus, e.g. guns
• CPC Class Codes: A61N 2005/0652 Arrays of diodes
• CPC Class Codes: B23K 26/0096 Portable laser equipment, e.g. hand-held laser apparatus surgical laser instruments A61B18/20, Dental Lasers A61C1/0046, Hand-held laser dental apparatus for curing resins A61C19/004
• CPC Class Codes: B23K 26/0608 in the same heat affected zone [HAZ] B23K26/0613, B23K26/0619 take precedence
• CPC Class Codes: B23K 26/064 by means of optical elements, e.g. lenses, mirrors or prisms
• CPC Class Codes: B23K 26/0643 comprising mirrors
• CPC Class Codes: B23K 26/0648 comprising lenses
• CPC Class Codes: B23K 26/0665 by beam condensation on the workpiece, e.g. for focusing
• CPC Class Codes: B23K 26/703 Cooling arrangements by using a fluid stream B23K26/14

Abstract

A curing light system useful for curing light activated composite materials is disclosed. Various configurations of light emitting semiconductor chips and heat sinks are disclosed, as well as various structures and methods for driving, controlling and using them.

Claims

1. A method for curing a composite material comprising the steps of:

providing a curing light that includes

a wand adapted to be grasped by a human hand for use in positioning and manipulating the curing light,

an elongate heat sink with a proximal end and a distal end, said proximal end being proximate said wand, said elongate heat sink having a longitudinal axis,

a mounting platform located at said elongate heat sink distal end, said mounting platform being adapted to have a LED chip module mounted on it, and

an LED chip module mounted on said mounting platform, said LED chip module including

a primary heat sink, said primary heat sink having a smaller mass than said elongate heat sink,

a well on said primary heat sink for mounting an LED chip,

an LED chip mounted in said well,

a cover that provides protective covering for said LED chip and which permits light emitted by said LED chip to pass through it to provide usable light exiting from said light module,

powering said LED chip with a pulsed current input at power level I in alternating periods of generally constant intensity current input to the chip followed by periods of rest with no current input in order to minimize heat effect on light output from the chip while maintaining non-pulsed light output from said LED chip,

permitting light to be output from the curing light;

applying said light to a material to be light cured;

wherein the curing light achieves an average power output level is greater than the power output level that would result from powering the same chip with a continuous current input at level I instead of pulsed current input, due to minimizing heat effect; and

wherein said LED chip is geometrically oriented with respect to said elongate heat sink longitudinal axis so that light emitted directly forward from the front of said LED chip travels in a direction that is at an angle of from about 30 degrees to about 150 degrees with respect to said longitudinal axis.

2. A method for curing a composite material comprising the steps of:

providing a curing light that includes

a wand adapted to be grasped by a human hand for use in positioning and manipulating the curing light, said wand having a longitudinal axis,

a secondary heat sink, said elongate heat sink having a longitudinal axis,

a primary heat sink attached to said secondary heat sink, and

a light emitting semiconductor chip attached to said primary heat sink,

powering said LED chip with a pulsed current input at power level I in alternating periods of generally constant intensity current input to the chip followed by periods of rest with no current input in order to minimize heat effect on light output from the chip while maintaining non-pulsed light output from said LED chip,

permitting light to be output from the curing light,

applying said light to a material to be light cured;

wherein the curing light achieves an average power output level is greater than the power output level that would result from powering the same chip with a continuous current input at level I instead of pulsed current input, due to minimizing heat effect; and

wherein said LED chip is geometrically oriented with respect to said elongate heat sink longitudinal axis so that light emitted directly forward from the front of said LED chip travels in a direction that is at an angle of from about 30 degrees to about 150 degrees with respect to said longitudinal axis.

3. A method as recited in claim 2 wherein said current I is between about 25 milliamps and 2 amps.

4. A method for curing a composite material comprising the steps of:

providing a curing light that includes

a wand adapted to be grasped by a human hand for use in positioning and manipulating the curing light, said wand having a longitudinal axis,

a primary heat sink, and

a light emitting semiconductor chip attached to said primary heat sink,

a plurality of epitaxial layers in said light emitting semiconductor chip,

at least one of said epitaxial layers being an active layer,

powering said LED chip with a pulsed current input at power level I in alternating periods of generally constant intensity current input to the chip followed by periods of rest with no current input in order to minimize heat effect on light output from the chip while maintaining non-pulsed light output from said LED chip,

permitting said current input to said chip to cause photons to be emitted by said active layer of said chip,

permitting said photons to exit the curing light as light, said light output from the curing light having an average power output level, and

applying said light to a material to be light cured;

wherein said light output average power level is greater than the light output power level that would result from powering said chip a continuous current input at level I instead of pulsed current input due to minimization of heat effect on said chip; and

wherein said LED chip is geometrically oriented with respect to said elongate heat sink longitudinal axis so that light emitted directly forward from the front of said LED chip travels in a direction that is at an angle of from about 30 degrees to about 150 degrees with respect to said longitudinal axis.