The laser emission of YAIO3:Er at 1.663 pm was investigated in order to find the best conditions with respect to crystal orientation, Er concentration. and output coupling. Using ten different laser rods the following optimised data have been obtained: b axis laser rod(Pnmanotation),1.25%Erdoping,and857~outputmirrorreflectivity.Thetemperature dependence of laser threshold and efficiency was measured between -50" and 50 "C. At room temperature we obtained34 J thresholdenergy and0.07% slope efficiency. In addition laser emission of LiYFJ:Ho, Er, Tm at 2.065 pm was investigated. The slope efficiency was 0.22%. Laser emission of YA103:Ho, Er, Tm at 2.12 pm is briefly mentioned.

To understand the mechanism of surface processing using atmospheric-pressure non-equilibrium plasma jets, we measured the vibrational and rotational temperatures in the plasmas by optical emission spectroscopy. Plasma was excited using a high-frequency pulsed power supply, using a gas mixture of Ar (20 L/min) and N2 (0.1 to 0.5 L/min) as the plasma gas, and changing the flow rate of N2 gas at an input power of 100 W and plasma frequencies of 5 and 10 kHz. The measured vibrational and rotational temperatures in plasma were approximately 0.18 to 0.26 eV and 0.21 to 0.28 eV, respectively. We also carried out a plasma surface processing of polyethylene naphthalate film to measure the changes in water contact angle before and after the processing. We found a monotonic decrease in the contact angle of the processed polyethylene naphthalate film as plasma rotational temperature increased. It is concluded that the hydrophilicity of the polyethylene naphthalate surface increases with plasma rotational temperature.