Measurement of gain in pump diode lasers using a low-coherence source and synchronous detection

Measurement of visual index in tunnels u

Measurement of visual index in tunnels using automatic gain controlled laser diodes and a homodyne detection scheme

✍ Jongtaek Park; Donghyun Seo; Bonjeong Koo; Youngil Park 📂 Article 📅 2004 🏛 Elsevier Science 🌐 English ⚖ 290 KB

A visual index measurement scheme that can be applied to a tunnel environment is proposed. To check the ventilation condition, a relative visibility is measured using a laser diode (LD) with wavelength of 880 nm. The LD is modulated with a 10 kHz sinusoidal signal to be used for a homodyne detection