| abstract |
PROBLEM TO BE SOLVED: To provide a short optical pulse amplifying device having a small size, a high intensity, a high reliability and a cost-effective performance. SOLUTION: The short light pulse amplifying device has been reduced in size, increased in strength and reliability, and improved in cost performance. The invention is particularly useful for chirped pulse amplification (CPA) systems where the pulse is stretched, amplified and recompressed. The compact expander 20 is used with a bulk compressor 40, in which a telescope is inserted into the collimated light path. A non-linear chirped Bragg grating may be made in the fiber stretcher. A fiber and a bulk amplifier may be used to amplify the pulse, and a doubling crystal may be inserted in the optical path of the pulse between the two amplifiers. The laser amplifier can be excited by the laser of the same material as the laser amplifier, but the excitation laser and the amplification laser operate under different conditions. |