The INTERFIRE-II 10.6 operates in the far IR waveband (8-12 microns) using a stabilised CO2 waveguide laser source operating at 10.6 microns. Alternative lasers are available for different wavelengths. The instrument can be used in development, test or production laboratories and is used for the accurate measurement of wavefront aberration of thermal imaging lenses, optical homogeneity of infra red materials and flatness of optical surfaces.

It features a focal plane array camera which is much more sensitive than previous cameras and has significantly reduced noise, allowing high quality images of fringes to be acquired quickly, easily and with no focus drift. When used with phase shifting fringe analysis software, the acquisition of fringes is much more reliable. The phase shifting technique used allows the highest degree of precision and enables full use of standard accessories.



Twyman-Green Unequal Path Interferometer


10.6 microns (others available)


675mm (l) x 260mm (w) x 280 mm (h)


35 kg approx

Laser source type


Water-cooled waveguide CO2 (others available)

Clear aperture

Nominally 35mm (greater than 31.5 mm guaranteed). Expandable with accessories

Fringe detection

Focal plane array with fringe contrast adjustments


CCIR compatible or as specific user requirements


Integral co-linear visible HeNe laser

Optical zoom

Continuously variable x1 - x3

Remote control

Full control of reference mirror tilt/tip

CO2 and HeNe lasers - on/off, standby,

aperture focusing, optical zoom,

Accuracy (PV)

STATIC: l/20     PHASE: l/50

Repeatability (PV)

STATIC: l/50     PHASE: l/1000

Data acquisition time

STATIC: 0.04 sec     PHASE: 0.167 - 1.33 sec

Minimum hardware

Pentium computer© with maths processor,

vacant expansion slot for framegrabber board







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