| 摘要 |
<p>A laser pump cavity apparatus (10) with integral concentrator provides improved thermal lensing control, cooling and fracture strength. The concentrator is formed around a doped solid-state laser medium by diffusion bonding, using a material different than the doped laser medium and with a substantially lower index of refraction, higher thermal conductivity and higher stress fracture strength than the doped laser crystal. The concentrator has a top cladding layer (46) with a cylindrical focusing surface (18) and a bottom cladding layer (48) with a cylindrical focusing surface (18) and may have edge cladding layers (50). Cold plates (24), each of which also has one cylindrical surface (22 and 45), are placed in thermal contact with the cylindrical surfaces of the top (46) and bottom (48) cladding layers. The cylindrical surfaces (46 and 48) preferably have hyperbolic or quasi-hyperbolic shaped. The laser pump cavity apparatus (10) is preferably pumped with several laser diode arrays (26) in directions transverse to a laser beam axis (12). The pumplight is injected from the laser diode arrays (26) through the edge cladding layers (50) in directions toward line foci (20) of the cylindrical surfaces (46 and 48). The concentrator top (46) and bottom (48) cladding material is preferably sapphire and the doped solid-state laser medium is preferably Yb:YAG. The edge cladding layers (50) are preferably thermally insulating to maintain a one-dimensional heat flow condition with the doped laser medium, by forming them of a material that has lower thermal conductivity than the material used for the top (46) and bottom (48) cladding layers. The edge cladding layers (50) are preferably made of undoped YAG material.</p> |
