[OPTICAL REVIEW Vol. 4, No. 4 (1997) 444-446]

Optical Dispersion Characteristics of Planar Microlenses

Rogerio Jun MIZUNO, Toshio KATO and Kenichi IGA

Precision and Intelligence Laboratory, Tokyo Institute of Technology, 4259, Nagatsuta, Midori-ku, Yokohama, 226 Japan

(Received January 6, 1997; Accepted May 30, 1997)

It is essential to know the wavelength dispersion of a planar microlens in order to suitably design optical systems which use such a component. For this purpose, the measurement of focal length over a wide range of the spectrum has been performed. It was clarified that the focal length varies by about 20% from blue (λ=0.442 μm) to near-infra red (λ=1.55 μm) region. The maximum index difference between the lens center and substrate, an important parameter for the characterization of planar microlenses, has been estimated as a function of wavelength using the ray equation. The effect of angled incidence has been discussed.

Key words : planar microlens, wavelength dispersion, focal length, ray equation, normalized index differenc