Phase plate technology for laser marking of magnetic discs

Patent · Thu Jan 01 00:00:00 EST 1998

OSTI ID:871942

Neuman, Bill ^[1]; Honig, John ^[1]; Hackel, Lloyd ^[1]; Dane, C Brent ^[1]; Dixit, Shamasundar ^[1]

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1. Livermore, CA

An advanced design for a phase plate enables the distribution of spots in arbitrarily shaped patterns with very high uniformity and with a continuously or near-continuously varying phase pattern. A continuous phase pattern eliminates large phase jumps typically expected in a grating that provides arbitrary shapes. Large phase jumps increase scattered light outside of the desired pattern, reduce efficiency and can make the grating difficult to manufacture. When manufacturing capabilities preclude producing a fully continuous grating, the present design can be easily adapted to minimize manufacturing errors and maintain high efficiencies. This continuous grating is significantly more efficient than previously described Dammann gratings, offers much more flexibility in generating spot patterns and is easier to manufacture and replicate than a multi-level phase grating.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
• DOE Contract Number: W-7405-ENG-48
• Assignee: Regents of University of California (Oakland, CA)
• Patent Number(s): US 5828491
• OSTI ID: 871942
• Country of Publication: United States
• Language: English

Related Subjects

phase
plate
technology
laser
marking
magnetic
discs
advanced
design
enables
distribution
spots
arbitrarily
shaped
patterns
uniformity
continuously
near-continuously
varying
pattern
continuous
eliminates
jumps
typically
expected
grating
provides
arbitrary
shapes
increase
scattered
light
outside
desired
reduce
efficiency
difficult
manufacture
manufacturing
capabilities
preclude
producing
easily
adapted
minimize
errors
maintain
efficiencies
significantly
efficient
previously
described
dammann
gratings
offers
flexibility
generating
spot
easier
replicate
multi-level
scattered light
continuous phase
phase plate
desired pattern
varying phase
previously described
phase grating
continuously varying
arbitrary shape
easily adapted
/359/219/430/