title: Dual-prism interferometer for collimation testing.
abstract: An air-wedge lateral-shear interferometer using two prisms is presented. With a variable shear, the interferometer is suitable for testing collimation of a wide range of beam sizes down to a few millimeters in diameter. No antireflection coatings are necessary. Collimation for a light source with short coherent length is also demonstrated.
authors.affiliation: Department of Physics, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: King Ung
authors.initials: KU
authors.lastname: Hii
authors.forename: Kuan Hiang
authors.initials: KH
authors.lastname: Kwek