Dual band lens system incorporating molded chalcogenide

A system comprising:

• a plurality of lens elements comprising at least one molded aspheric chalcogenide lens element having an associated Abbe number V3-13 in the range from about 47.799 to 47.837 calculated as:
• V3-13=(N8−1)/(N3−N13)
• where N8 is the refractive index at a wavelength of 8 micrometers, N3 is the refractive index at a wavelength of 3 micrometers and N13 is the refractive index at a wavelength of 13 micrometers, said plurality of lens elements configured to simultaneously image light in a wavelength range from about 3 to about 5 micrometers and light in a wavelength range from about 8 to about 12 micrometers at a common focal plane;
• a detector positioned at said common focal plane and configured to create electrical impulses in response to said light in said wavelength range from about 3 to about 5 micrometers and said light in said wavelength range from about 8 to about 12 micrometers;
• and
• a signal processing unit configured to process said electrical impulses for displaying an

A method comprising:

• imaging light in a wavelength range from about 3 to about 5 micrometers and light in a wavelength range from about 8 to about 12 micrometers at a common focal plane using a plurality of lens elements comprising at least one molded aspheric chalcogenide lens element having an associated Abbe number V3-13 in the range from about 47.799 to 47.837 calculated as:
• V3-13=(N8−1)/(N3−N13)
• where N8 is the refractive index at a wavelength of 8 micrometers, N3 is the refractive index at a wavelength of 3 micrometers and N13 is the refractive index at a wavelength of 13 micrometers;
• and
• displaying an image in response to said light at said common focal plane.