CO, HF and DF laser spectrum analyzer
Macken Instruments offers Laser Spectrum Analyzers calibrated for use with CO, HF and DF Lasers similar to our CO2 Laser Spectrum Analyzer. Additional general information can be obtained by reviewing the Model 16-A data sheet.
Model 16-B(CO) and 16-C(CO)
Two different Spectrum Analyzers are offered for CO lasers. As seen from the specifications, Model 16-C(CO) has higher resolution, but a narrower spectral range than Model 16-B(CO). The spectral range of 4.8 µm to 5.9 µm of the Model 16-C(CO) covers the wavelengths of almost all continuous CO lasers.
Although literature references quote wavelengths beyond this range (which can be viewed with the 16-B(CO), these are usually observed only in pulsed operation or with wavelength selective laser mirrors. The greater resolution obtained by reducing the spectral range proves to be convenient in the majority of applications.
The Model 16-B, has the added feature that it can be used for HF lasers merely by replacing the calibrated wavelength scale with an HF scale (sold separately). This converts the unit to a Model 16-B(HF).
All of the above-mentioned models are calibrated by both wavelength and wave number.
As previously stated, the HF and CO scales are interchangeable in Model 16-B series Spectrum Analyzers. Therefore, it is possible to order separately a CO Laser scale for this model.
The calibrated scale in this unit designates wavelength and laser transitions. The transitions identified are:
1 -> 0 band P(5) to P(12); 2 -> 1 band P(4) to P(13); 3 -> 2 band P(4) -> P(13).
These Spectrum Analyzers come equipped with two different Thermal Sensitive Display Screens referred to as screens #7 and #8. The screens differ in sensitivity, response time, and resolution. Their characteristics correspond to surfaces #7 and #8 on Macken Instruments' Thermal Image Plates and Beam Probes. Screen #8 is more sensitive than screen #7 and is useful for detecting weak rotational lines. However, screen #8 has lower resolution and a longer time constant. Its greater sensitivity is also often useful when dealing with low energy pulses.
These display screens can simultaneously exhibit lines which differ in power density by a factor of ten. when this density range is not wide enough, provisions are made in the Spectrum Analyzer to block the strongest of the rotational lines. This prevents damage to the display screen when the slit is open wide enough to display the weakest of the rotational lines.
Since the CO, HF and DF lasers may run in many rotational lines simultaneously, it is possible to have the weakest of these lines contain only about 1% of the total power. Although the Spectrum Analyzer is capable of displaying individual rotatational lines at power levels down to milliwatts, it is recommended that the total laser power exceed 1 watt so that it is possible to observe the weakest rotational line.
Should the display screen ever become damaged, it is possible to expose an unused surface by rotating the screen. Additional screens can be purchased, and calibrated wavelength scales for converting Model 16-B(CO) to Model 16-B(HF), or vice versa, are also available. The CO scales are Model 16-WSCO and the HF scales are Model 16-WSHF.
|Specifications common to all models|
|Maximum Power (continous duty)||75 watts|
|Minimum Power (focused single wavelength)||0.03 watts* (Screen #7)|
0.01 watts (Screen #8)
|Response Time||25 sec. (Screen #7)|
1.0 sec. (Screen #8)
|Dimensions||45,7 x 25,2 x 16,5 cm (LxBxH)|
|Elevation of Slit||5,7 to 9,7 adjustable|
|Electric Power||230V, 50HZ, 10 watts|
|*CO and HF wavelengths may require more power than this if the particular line is strongly absorbed by atmospheric water vapor. The water vapor content within the Spectrum Analyzer can be reduced by flushing the instrument with dry nitrogen or using a desiccant.|
|Wavelength Range||2.45 to 3.25 µm||4.9 to 6.5 µm||4.8 to 5.9 µm||3.5 to 4.2 µm|
|Wave Number Range||4080 to 3100 cm-1||2040 to|
|Resolution with Screen #7||0.0012 µm||0.0024 µm||0.0016 µm||0.0010 µm|
|Resolution with Screen #8||0.0024 µm||0.0048 µm||0.0032 µm||0.0020 µm|
|Calibrations on Scale||Wavelength and|
|Wavelength and Wave Number||Wavelength and Wave Number||Wavelength & Vibrational-|