These slightly bluish glass filters feature high transmittance in the visible region and good absorption of heat rays (infrared rays).
The latter efficiently absorb thermal radiations emitted from a light source, and so are highly effective when employed for slide projectors and a variety of illumination equipment.
Note: " Strengthened glass, " produced by tempering processes, may also be supplied to minimize the cracking of filter glass due to thermal shock.
HA-15
15% Absorbing heat radiation 3.0 mm
HA-30
30% Absorbing heat radiation 3.0 mm
HA-50
50% Absorbing heat radiation 3.0 mm