Output characteristics of actively Q-switched Ho:LuVO4 laser at room temperature.

A compact continuous wave (CW) and actively Q-switched (AQS) Ho:LuVO4 laser pumped by a 1.94 µm Tm: YAP laser is demonstrated. The performance of the laser was investigated by changing the output coupler. The maximum output power of 4.1 W at 2058.43 nm in CW regime is obtained at the maximum absorbed pump power of 12.3 W. The minimum pulse width of 29.3 ns was obtained at Pulse Repetition Frequency (PRF) of 20 kHz with the same output coupler corresponding to a peak power of 6.9 kW. The maximal output power is 4.1 W with center wavelength of 2058.43 nm at PRF of 40 kHz, corresponding to slope efficiency of 43.0% with respect to absorbed pump power. The M2 factors measured by the traveling knife-edge method are 1.04 in parallel a-axis and 1.08 in parallel c-axis with diffraction limited beam quality.

Efficient Q-switched Ho:GdVO4 laser resonantly pumped at 1942 nm.

An efficient 2 µm room-temperature Q-switched Ho:GdVO4 laser end-pumped by a 1942 nm Tm-fiber laser is demonstrated. To our knowledge, this is the first report of Q-switched performance of Ho:GdVO4 crystal. A maximum CW output power of 6.85 W under the absorbed pump power of 24.1 W was obtained with a slope efficiency of 39.5% at a temperature of 17°C. With the same absorbed pump power, a maximum output energy per pulse of about 0.9 mJ and minimum pulse width of 4.7 ns were obtained at the pulsed repetition frequency (PRF) of 5 kHz, corresponding to a peak power of approximately 187.2 kW.

Room temperature single longitudinal mode laser output at 1645 nm from a laser-diode pumped Er:YAG nonplanar ring oscillator.

We report on a monolithic 1645 nm Er:YAG nonplanar ring oscillator (NPRO) resonantly pumped by a fiber-coupled laser diode. In the experiment, an up to 550 mW single frequency laser output at 1645.2 nm was obtained, corresponding to a slope efficiency of 19.1% and an absolute efficiency of 6.0%. The beam quality M2 was measured to be 2.1 at the highest output power.

Single-frequency, Q-switched Ho:YAG laser at room temperature injection-seeded by two F-P etalons-restricted Tm, Ho:YAG laser.

We demonstrated a 1.91 µm pumped, injection-seeded Q-switched Ho:YAG laser operating at room temperature. By inserting two Fabry-Perot etalons into the laser cavity, single-frequency Tm, Ho:YAG seed lasing was achieved at a wavelength of 2090.9 nm, with a typical output power of 60 mW. Single-frequency, nearly transform-limited Q-switched operation of the Ho:YAG laser was achieved by injection seeding. The output energy of the single-frequency Q-switched pulse is 7.6 mJ, with a pulse width of 132 ns and a repetition rate of 100 Hz. We measured the pulse spectrum, half-width of which was 3.5 MHz, by a heterodyne technique.

[Immunological study of inefficiency schizophrenics with deficiency syndrome treated with xin shen ling].

This paper reports 30 cases of chronic schizophrenics with deficiency syndrome who had chronically taken many sorts of neuroleptic medications and other therapies to be ineffective. The 7 immunological functioning markers were detected: phytohemagglutinin (PHA) intradermic test; circulating immune complex (CIC); T, B lymphocytes, null (N), double (D) cell; and large granular lymphocyte (LGL) and to be compared with a control group of 30 healthy individual. The result showed that 6 immunological markers (PHA, CIC and T, B, N and D cell) were significantly different as compared with the control group (P less than 0.01). In order to regulate proportion and function to immune cell, the 30 patients were given to take immuno-modulating herbs (xin shen ling, XSL) during 6 weeks, while their 7 immunological markers were detected before treatment (BT) and after treatment (AT). The results showed that 5 immunological markers (PHA, CIC, T, N, and D cell) of BT were significantly different as compared with that of AT (P less than 0.01). However, the 5 immunological markers (PHA, CIC, and T, N and D cell) of AT were not significantly different as compared with that of the control group (P less than 0.05). The brief psychosis rating scale (BPRS) and nurses observation scale for inpatient evaluation (NOSIE) were used as evaluating changes of clinical symptoms BT and AT. The results showed that BPRS and NOSIE of BT were significantly different as compared with that of AT (P less than 0.05). The clinical efficacious rate was 67%. We have followed up the results for near 3 years which had a relapse of 5 cases of 20 cases be discharged. It seemed that XSL may be one of the preventive relapse agent for these patients.