It is achromatic lens having a negative focal length.
By setting the concave one bonding two lenses wavelength dispersion of the refractive index is different, can be smaller than the spherical single lens and spherical aberration and chromatic aberration.
• It is optimized focal length shift is small in the visible light range, the aberration is minimized.
• It can be the beam expander of Galileo type in combination with achromatic lens with a focal length of the positive.
• It is also corrected for astigmatism and comatic aberration off-axis as well as aberration of axial object point.
• For custom focal lengths and diameter sizes not listed on-line or in our catalog please contact our Sales Team.
• There is a direction to the incident parallel light to the achromatic lens. A surface with a small radius of curvature is allowed to be incident parallel light from a rear surface (the surface on the arrow is pointing to). When it is incident parallel light from the opposite side, spherical aberration and chromatic aberration will occur and the focused spot size will increase.
• When used in the visible region, spherical aberration and chromatic aberration increases. In addition, the transmittance decreases.