Broadband Mid-IR polarizers

Features

	Extremely broadband
	Wide acceptance angle
	Compact and portable
	Polyethylene polarizers for 20-1000 microns are also available!

Description

Holographically or mechanically ruled Polarizers operating in the range of 1-35 microns

A fine array of parallel conducting wires whose period is smaller compared to the wavelength of incident radiation will transmit one polarisation and reflect the other. The component of the radiation whose electric vector is perpendicular to the direction of the wires and induces current in the wires will be transmitted and the parallel vector
reflected. Altechna's Mid-IR polarizers are produced by holographic method (i.e. laser interferometry) or mechanically ruled. These polarisers do not suffer from beam displacement, are not affected by diverging or converging beam,
have wide acceptance angle without degradation of performance and portable.

Standard Specifications

Dimensional tolerances	+0/-0,5mm
Parallelism error	<5arcmin
Surface finish	80-50 SD (for holographic type)
Surface flatness	<3 fringes/inch @633nm
Laser damage threshold of Holografic type polarizers	>50W/cm2 CW or >0,7J/cm2 100ns pulsed
Laser damage threshold of Mechanically ruled polarizers	>120W/cm2 CW or >2J/cm2 100ns pulsed

Performance table

Material	Spectral range (um)	Transmission efficiency, % (k1) ; (k2)	Degree of polarisation, % (k1-k2) / (k1+k2)	Extinction ratio (k1/2k2)	Contrast ratio (k1/k2)	Type
KRS-5	2-35 microns	(k1>75%; k2<0,7%)@3um ; (k1>71%; k2<0,3%)@15um	98,2%@3um ; 99,2%@15um	54:1@3um ; 118:1@15um	108:1@3um ; 236:1@15um	Holographic
CaF2	1-10 microns	(k1>85%; k2<0,7%)@3um ; (k1>80%; k2<0,24%)@8um	98,4%@3um ; 99,4%@8um	61:1@3um ; 165:1@8um	122:1@3um ; 330:1@8um	Holographic
BaF2	1-13 microns	(k1>85%; k2<0,58%)@3um ; (k1>85%; k2<0,23%)@10um	98,6%@3um ; 99,5%@10um	73:1@3um ; 185:1@10um	146:1@3um ; 370:1@10um	Holographic
ZnSe	1-16 microns	(k1>70%; k2<0,6%)@3um ; (k1>72%; k2<0,22%)@10um	98,3%@3um ; 99,4%@10um	58:1@3um ; 163:1@10um	116:1@3um ; 326:1@10um	Holographic
CaF2	1-9 microns	(k1>70%; k2<0,7%)@3um	>98%@3um	>50:1@3um	>100:1@3um	Mechanically ruled
ZnSe	1,5-14 microns	(k1>70%; k2<1,4%)@3um	>97%@3um	>25:1@3um	>50:1@3um	Mechanically ruled