IR Optical Components

Silicon windows, Silicon lenses, Silicon optics


Optical grade Silicon is normally specified with a resistivity of 10 to 40 Ohm-cm which is higher than most semiconductor applications. The usual Silicon material, unless otherwise specified is CZ, Czochralski Grade which has a Si-O absorption band at 9μm and so not important if the windows are used in the 3 to 5μm thermal band. Where required FZ, Float Zone material can be supplied which does not have this absorption.


Very high resistivity material can be supplied on special order, particularly for TeraHertz applications.


Silicon is used for windows and lenses in the 2-7µm range, ideal choice for IR LED lenses. The refractive index is near 3.4 throughout the range. Silicon high thermal conductivity and low weight are attractive features in IR or FTIR applications. Silicon is also used as a high reflectivity mirror for lasers and for IR silicon viewports.


ChangChun Long Ze Precision Optics Co.,Ltd - manufacturer of Silicon lenses for Thermal Imaging, Pyrometry and IR LED.

Low Dispersion and Density

Transmission from 1.2 to 7µm

High resistivity hemispherical lens avaialable

Available with AR or DLC coating for 3-5µm

Custom Silicon lenses - Available in a wide variety of diameters and focal lengths



ChangChun Long Ze Precision Optics Co.,Ltd offers custom of optical lenses and optical systems according to customer’s design. No matter how many you demand, please contact with us: We will kindly reply in an instant message.