Achromatic lenses are lenses consisting of two or more elements, which are usually made of crown and flint glass with differing indices of refraction. One element is positive, the other is negative. Distinct wavelengths can be corrected for chromatic aberration.
Achromatic lenses are nearly free from aspherical aberration and coma. Comparing with singlet lenses, achromatic lenses have far superior optical performance.
Bond with glue NOA61 (produced by Norland)
The glue can withstand temperatures from -150℃ to 125℃.
Refractive Index of Cured Polymer is 1.56, and transparence from 0.34μm to 2.0μm.
Please go to Norland website for more information of the glue.