OVERVIEW
Calomel is suitable for the construction of acousto-optical devices. To illustrate, Calomel´s AO figure of merit is comparable with that of a tellurium dioxide TeO2 and more than one order better than that of lead molybdenate PbMoO4. The transparency of Calomel (0.38 to 20µm) enables the use of AO units in a broad spectral range (compared with TeO2) covering a very interesting thermal IR region. No acousto-optical tuneable filter for interesting spectral TIR region is currently available on the market.
POSSIBLE APPLICATIONS
AOTF
Calomel properties make it a great candidate for production of acousto-optical tuneable filters (AOTF). The AOTF may be exploited as broadband “dispersive medium” which benefits of large wavelength operative range, interferometer-like spectral resolution, compact design and no moving parts. Hyperspectral imagers based on the AOTF for TIR region, have a wide range of potential applications such as atmospheric gas detection, water management, fire hazards, volcano monitoring, astronomy, oil spills detection, surveillance, etc.
DELAY LINES
Calomel, as a medium for delay of acoustic waves offers the longest possible time window (up to l50 µsec) of any known material. Such a slow shear acoustic wave can significantly reduce the size of generally used delay lines. Such a property makes Calomel ideal for signal processing – correlation, convolution and filtering, noise reduction, etc.
Comparission of Paratellurite and Calomel for AO applications
Material | TeO2 | Hg2Cl2 |
---|---|---|
Refractive indices @589nm |
2.26(o), 2.41(e) | 1.9(o), 2.6(e) |
Birefringence @589nm |
0.15 | 0.7 |
Sound velocity in the [110] direction [m/s] | 620 | 347 |
Possible frequency bandwidth at 100 MHz [MHz] | 45-47 | 20-25 |
Achievable resolution with 5 mm aperture [points] | 37 | 330 |
Figure of merit in the [110] direction M2 [x10-18 s3/g] | 370 | 800 |

Interested in Calomel AO components? Please contact us on info(at)calomel.cz for inquiry.