Radiation shield device and method

A shield having an irradiance damage threshold IDT for protecting a tool portion from damage due to high-irradiance radiation IR from a light source when irradiating a workpiece, said shield arranged between the light source and the tool portion and having a volume damage threshold IDS, an absorption coefficient a, and a thickness t such that an irradiance IABS absorbed by said shield from said high-irradiance radiation IR that would otherwise be incident the tool portion satisfies the condition:

• IABS=IR a (1−exp(−at))<IDS,
• and wherein radiation exiting the shield and incident the tool portion has an irradiance IT which satisfies the condition:
• IT=IR (exp(−at))<IDT.

A shield for protecting a tool portion having an irradiance damage threshold from high-irradiance radiation from a light source when irradiating a workpiece, said shield arranged between the light source and the tool portion and having an irradiance damage threshold, a scattering coefficient, a volume and a thickness, and designed to scatter in said volume portion of said high-irradiance radiation that would otherwise be incident said tool portion, wherein said shield maintains said scattered high-irradiance radiation below said shield irradiance damage threshold, and wherein radiation exiting the shield and incident the tool portion has an irradiance below the irradiance damage threshold of the tool portion.

A shield for protecting a tool portion having an irradiance damage threshold IDT from damage due to high-irradiance radiation IR from a light source when irradiating a workpiece, said shield arranged between the light source and the tool portion and separated from the tool portion by a distance d, and having a scattering coefficient Θ, a scattering area A and a thickness t, wherein radiation exiting the shield and incident the tool portion has an irradiance IT satisfying the condition:

• IT=IR A/(Θd2)<IDT.

A shield for protecting a tool portion having an irradiance damage threshold from high-irradiance radiation from a light source wherein irradiating a workpiece, said shield arranged between the light source and the tool portion and having an irradiance damage threshold, an absorption coefficient, a volume, a scattering coefficient and a thickness, wherein said shield is designed to absorb and scatter in said volume a portion of the high-irradiance irradiation, wherein the shield maintains said absorbed high-irradiance radiation below said shield irradiance damage threshold, and wherein radiation exiting the shield and incident the tool portion has an irradiance below the irradiance damage threshold of the tool portion.

A shield for protecting a tool portion having an irradiance damage threshold IDT, from damage due to high-irradiance radiation of irradiance IR from a light source when irradiating a workpiece, said shield arranged between the workpiece and the tool portion and separated from the tool portion by a distance d, and having an irradiance damage threshold IDS, an absorption coefficient a, a scattering coefficient Θ, a scattering area A, and a thickness t such that an irradiance IABS absorbed by said shield from the high-irradiance radiation satisfies the condition:

• IABS=IR a (1−exp(−at)),
• and radiation transmitted through the shield and incident the tool portion has an irradiance IT satisfying the condition:
• IT=IR (exp(−at)) A/(d2Θ).

A method of attenuating high-irradiance radiation from a light source incident a tool portion of a tool while processing the workpiece, the tool portion having an irradiance damage threshold, the method comprising the steps of:

• a) arranging a shield between the light source and the tool portion, said shield having a volume and capable of absorbing a portion of the high-irradiance radiation within said volume;
• and
• b) absorbing a portion of the high-irradiance radiation that would be incident the tool portion within said volume of said shield so that radiation leaving said shield and incident said tool portion has an irradiance below the irradiance damage threshold of the tool portion.

A method of attenuating high-irradiance radiation from a light source incident a tool portion of a tool while processing the workpiece, the tool portion having an irradiance damage threshold, the method comprising the steps of:

• a) arranging a shield between the light source and the tool portion, said shield having a volume and capable of scattering a portion of the high-irradiance radiation within said volume;
• and
• b) scattering a portion of the high-irradiance radiation that would be incident the tool portion within said volume of said shield so that radiation leaving said shield and incident said tool portion has an irradiance below the irradiance damage threshold of the tool portion.

A method of attenuating high-irradiance radiation from a light source incident a tool portion of a tool while processing the workpiece, the tool portion having an irradiance damage threshold, the method comprising the steps of:

• a) arranging a shield between the light source and the tool portion, said shield having a volume and capable of absorbing and scattering a portion of the high-irradiance radiation within said volume;
• and
• b) absorbing and scattering a portion of the high-irradiance radiation that would be incident the tool portion within said volume of said shield so that radiation leaving said shield and incident said tool portion has an irradiance below the irradiance damage threshold of the tool portion.