A Passive Q-switching is a device that can accomplish Q-switching by taking advantage of the truth that the passage of optical material relies on the laser intensity at a specific wavelength. The laser freeze linker mainly generates saturated absorbent crystals in passive Q-switched crystals. The absorption coefficient of saturated absorption crystal lowers with the rise of incident light intensity. When the saturation value is gotten to, the loss (Q worth) in the laser dental caries is modulated, and the pulse is given off.
Passive Q-switching crystals
Co: Spinel
Co: Spinel crystal, named cobalt spinel, is a freshly created material. Its discharging wavelength variety is 1.2-1.6 μm, which has actually proved to be an extremely effective passive Q-switching switch. It is widely made used in the eye-safe Er: glass laser (1.54 µm) as well as has actually been validated in lasers with wavelengths of 1.44 µm as well as 1.34 µm. Co: Mgal2o4( Co: spinel) has a high absorption cross-section, making it possible for Q switching of Er: glass lasers (flash and also diode laser pumps) without tooth cavity concentrating. The negligible ecstatic state absorption leads to a high comparison ratio of the Q switch. That is, the proportion of the first to saturated taken in signal is higher than 10.
The main features of Co: Spinel crystal:
- 1.3 to 1.6 mu m within the range of the low optical loss
- high damage threshold
- Main applications of Co: Spinel crystals:
- passive q-switched @ 1.54 microns
V: YAG
V: YAG crystal, the Chinese name vanadium-doped yttrium aluminum garnet, is a reasonably new crystalline material. Ideal for 1.06 ~ 1.44 μm laser emission, especially for 1.3 μm Nd laser. The absorption peak cross-section of the thrilling state is not noticeable near the absorption peak of 1300 nm. This material has excellent optical, mechanical as well as thermal buildings. It can be produced by the Czochralski method. V: YAG crystals can be used in Nd: YAG, Nd: YAP, Nd: KGW, Nd: YVO 4, and other energetic media to obtain the passive Q-switching laser with compact structure and also superb performance.
V: YAG crystal Main qualities:
- High-ground state absorption
- Not noticeable ecstatic state absorption
- Q-switch high contrast
- Great optical residential or commercial properties, mechanical residential or commercial properties, and thermal homes
- Ultraviolet-resistant high damages limit
V: YAG crystal Main application:
- Used in laser rangefinders, laser radar as well as the passive tuning Q laser LIBS system
Cr: YAG
Cr4+: YAG crystal, Chinese name chromium doped yttrium aluminum garnet, is an excellent product for Q-switching of laser (Nd: YAG as well as various other doping Nd or Yb) with wavelengths from 0.8 to 1,2 μm. A notable function of Cr4+: YAG is its high damage threshold of 500-1000 MW/cm2. Its absorption band expands from 800 nm to 1200 nm as well as reaches its optimal at about 1060nm, with a very large cross-sectional area of absorption top.
Cr: YAG crystal Main features:
- 500-1000 MW/cm2 high damage threshold
- Extremely steady chemical as well as reliability
- Good thermal conductivity, long life span
- Small passive Q switch
- Simple to operate
Cr: YAG crystal Main application:
- Made use of laser range finder, LIDAR, and also LIBS passive adjusting Q laser system
- Require a brief pulse laser system
Cr: YSO
In 1991, it was found that Cr: YSO( pure tetravalent chromium collection) solid-state saturable absorbing could be used for laser applications.
In 1993, Chen et al. used Cr: YSO solid-state saturable absorber to effectively act on a 694.5 nm ruby laser,
The crystals’ wide-band absorption range (peaking at 390 nm, 595 nm, 695 nm, and 750 nm) prolongs from the noticeable region to the near-infrared area, making it an excellent switch for many lasers.
Cr: GSGG
Cr4+: GSGG can be used as a passive Q-switching in the 1.06 μm band. Compared to the traditional Cr4+: YAG passive Q-switched crystal, Cr4+: GSGG crystal has the following benefits:
The visible component is transparent (calibration) as well as is much more beneficial to the laser light path,
In 1.06 mu m band have a greater absorption coefficient. At the same time, it also has a solid capability for anti-irradiation.