Steinheil Cemented
Achromatic Triplets

The focal point where light rays passing through the center of the lens converge differs slightly from the focal point where light rays passing through the edges of the lens converge, this is called spherical aberration; when light rays pass through a convex lens, the focal point for red light which has a long wavelength is farther away than the focal point for blue light which has a short wavelength, as a result colors appear to bleed, this is called chromatic aberration. Since the direction in which spherical aberration occurs in a convex lens is opposite to a concave lens, through a combination of two or more lenses light rays can be made to converge to a single point, this is called aberration correction. Achromatic lenses correct for both chromatic and spherical aberrations. Our standard and custom achromats are designed and manufactured to satisfy the most stringent tolerances required in today’s high-performance laser, electro-optical and imaging systems.