The PDT device uses photochemical reactions of photosensitive substances to produce reactive oxygen species, which can damage tumor cells and cause tumor cells to degeneration and necrosis, while normal cells can absorb the laser, this is called photodynamic therapy. Normal cells metabolize faster than tumor tissues, so normal cells are almost unaffected and can be selectively treated for cancer with small side effects after operation.The PDT device limits the absorption wavelength of the photosensitive substance to 620-670nm. The YAG-OPO laser has the wavelength variability corresponding to the absorption wavelength of the new photosensitive material.
Theotry
The main components of device are:
Gain medium - Nd YAG
Nd:YAG produces a fundamental wave of 1064 nm.
BBO nonlinear crystals are very powerful in OPO, it can produce a series of tunable rays from ultraviolet to infrared, and BBO crystals achieve higher energy conversion rates.
BBO Nonlinear crystals
Double-frequency high-frequency wave (called SHG), which is converted 1064nm into 532 nm, and triple-frequency high -frequency wave (called THG), which is converted 1064nm into 355 nm.
Feature
- Selective treatment
- Small surgical side effects
- Small damage
Application
- Photodynamic therapy
- Treatment of lung cancer
- Treatment of esophageal cancer
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