Fabrication of diffractive-optical elements by using halftone gray-scale masks

Jinsong Liu, Andrew J. Waddie, Mohammad R. Taghizadeh

Research output: Contribution to journalArticle

Abstract

The fabrication of diffractive optical elements (DOEs), especially the DOEs with variable spatial frequency features, by using halftone gray-scale masks is investigated. Three aspects of the DOEs profile infidelity have been studied. The first two infidelities are, with the reduced periods, the decrease in maximum depth in photoresist and the increase in relative transition width between adjacent ramps. Imaging error is found to be responsible for the infidelities. The infidelities can be reduced by using a certain aperture or a larger photoreduction, while proximity-printing nearly eliminates the infidelites. The third infidelity is the uncertainty of the nonlinearity between the gray values in mask data and the final depth in photoresist. Both the nonlinearity and the uncertainty of the nonlinearity can be reduced to some extent by using a reduced gamut of gray values of 0.3-0.8 and an appropriate exposure dose from the primary mask to the secondary mask before the compensation function is finally measured and imposed on the gray-scale values. © 2002 Published by Elsevier Science B.V.

Original languageEnglish
Pages (from-to)31-40
Number of pages10
JournalOptics Communications
Volume208
Issue number1-3
DOIs
Publication statusPublished - 1 Jul 2002

Fingerprint

gray scale
masks
fabrication
nonlinearity
photoresists
ramps
printing
photochemical reactions
proximity
apertures
dosage
profiles

Keywords

  • Binary optics
  • Diffractive optics
  • Gray-scale
  • Optical fabrication

Cite this

Liu, Jinsong ; Waddie, Andrew J. ; Taghizadeh, Mohammad R. / Fabrication of diffractive-optical elements by using halftone gray-scale masks. In: Optics Communications. 2002 ; Vol. 208, No. 1-3. pp. 31-40.
@article{a2879bae32cd4fd893794c748372db34,
title = "Fabrication of diffractive-optical elements by using halftone gray-scale masks",
abstract = "The fabrication of diffractive optical elements (DOEs), especially the DOEs with variable spatial frequency features, by using halftone gray-scale masks is investigated. Three aspects of the DOEs profile infidelity have been studied. The first two infidelities are, with the reduced periods, the decrease in maximum depth in photoresist and the increase in relative transition width between adjacent ramps. Imaging error is found to be responsible for the infidelities. The infidelities can be reduced by using a certain aperture or a larger photoreduction, while proximity-printing nearly eliminates the infidelites. The third infidelity is the uncertainty of the nonlinearity between the gray values in mask data and the final depth in photoresist. Both the nonlinearity and the uncertainty of the nonlinearity can be reduced to some extent by using a reduced gamut of gray values of 0.3-0.8 and an appropriate exposure dose from the primary mask to the secondary mask before the compensation function is finally measured and imposed on the gray-scale values. {\circledC} 2002 Published by Elsevier Science B.V.",
keywords = "Binary optics, Diffractive optics, Gray-scale, Optical fabrication",
author = "Jinsong Liu and Waddie, {Andrew J.} and Taghizadeh, {Mohammad R.}",
year = "2002",
month = "7",
day = "1",
doi = "10.1016/S0030-4018(02)01564-X",
language = "English",
volume = "208",
pages = "31--40",
journal = "Optics Communications",
issn = "0030-4018",
publisher = "Elsevier",
number = "1-3",

}

Fabrication of diffractive-optical elements by using halftone gray-scale masks. / Liu, Jinsong; Waddie, Andrew J.; Taghizadeh, Mohammad R.

In: Optics Communications, Vol. 208, No. 1-3, 01.07.2002, p. 31-40.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Fabrication of diffractive-optical elements by using halftone gray-scale masks

AU - Liu, Jinsong

AU - Waddie, Andrew J.

AU - Taghizadeh, Mohammad R.

PY - 2002/7/1

Y1 - 2002/7/1

N2 - The fabrication of diffractive optical elements (DOEs), especially the DOEs with variable spatial frequency features, by using halftone gray-scale masks is investigated. Three aspects of the DOEs profile infidelity have been studied. The first two infidelities are, with the reduced periods, the decrease in maximum depth in photoresist and the increase in relative transition width between adjacent ramps. Imaging error is found to be responsible for the infidelities. The infidelities can be reduced by using a certain aperture or a larger photoreduction, while proximity-printing nearly eliminates the infidelites. The third infidelity is the uncertainty of the nonlinearity between the gray values in mask data and the final depth in photoresist. Both the nonlinearity and the uncertainty of the nonlinearity can be reduced to some extent by using a reduced gamut of gray values of 0.3-0.8 and an appropriate exposure dose from the primary mask to the secondary mask before the compensation function is finally measured and imposed on the gray-scale values. © 2002 Published by Elsevier Science B.V.

AB - The fabrication of diffractive optical elements (DOEs), especially the DOEs with variable spatial frequency features, by using halftone gray-scale masks is investigated. Three aspects of the DOEs profile infidelity have been studied. The first two infidelities are, with the reduced periods, the decrease in maximum depth in photoresist and the increase in relative transition width between adjacent ramps. Imaging error is found to be responsible for the infidelities. The infidelities can be reduced by using a certain aperture or a larger photoreduction, while proximity-printing nearly eliminates the infidelites. The third infidelity is the uncertainty of the nonlinearity between the gray values in mask data and the final depth in photoresist. Both the nonlinearity and the uncertainty of the nonlinearity can be reduced to some extent by using a reduced gamut of gray values of 0.3-0.8 and an appropriate exposure dose from the primary mask to the secondary mask before the compensation function is finally measured and imposed on the gray-scale values. © 2002 Published by Elsevier Science B.V.

KW - Binary optics

KW - Diffractive optics

KW - Gray-scale

KW - Optical fabrication

UR - http://www.scopus.com/inward/record.url?scp=0036665994&partnerID=8YFLogxK

U2 - 10.1016/S0030-4018(02)01564-X

DO - 10.1016/S0030-4018(02)01564-X

M3 - Article

VL - 208

SP - 31

EP - 40

JO - Optics Communications

JF - Optics Communications

SN - 0030-4018

IS - 1-3

ER -