Page 241 - High Power Laser Handbook
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210 So l i d - S t at e La s e r s Nd:YAG Ceramic ThinZag® High-Power Laser Development 211
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(a) (b)
Figure 9.3 Double-pass interferometer measurements show that Nd:YAG ceramic
slabs are intrinsically more uniform (b) than typical crystals (a).
two-pass interferometer comparing Nd:YAG crystal with Nd:YAG
ceramic slabs are shown in Fig. 9.3. The ceramic slab’s index of refrac-
tion uniformity was found to be generally superior. Although some
crystalline slabs were close in quality to the ceramic slabs, the index
variations from one crystal sample to another were significant and
unpredictable.
Measurements of laser output using a stable optical cavity veri-
fied that ceramic and crystalline slabs of Nd:YAG produced the same
output power, within experimental error (~1.2 kW), thus confirming
that ceramic gain material was suitable for high-power laser opera-
tion. Typical output power measurements are shown in Fig. 9.4.
1400
1200
1000
Power (W) 800 Ceramic slab
600
Crystal slab
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200
0
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Time (s)
Figure 9.4 Comparison of ceramic and crystal slab laser performance.
