Abstract: An airspaced, diffraction limited, seven element telecentric f-theta lens having a first meniscus lens concave to the incident side; a first bi-concave lens; a second meniscus lens convex to the incident side; a third meniscus lens concave to the incident side; a pair of bi-convex lenses; and a second bi-concave lens is disclosed. The second, third and fourth as well as the sixth and seventh lens elements are edge contact spaced.

Abstract: An air spaced reverse telephoto objective lens for use in a laser chemical vapor deposition system or the like having a quartz plate window. The objective lens includes a negative component having a first air-spaced doublet wherein each doublet element is made of crown glass and a negative meniscus crown glass element spaced from said first air-spaced doublet. The objective lens further includes an aperture stop, a positive component including second and third doublet components for effecting color correction, and a pair of bi-convex elements for effecting spherical aberration correction. The objective lens provides a common focal plane for both illuminating light and laser light passing through the objective lens and the quartz plate window.