The light source
Different types of light source lamps in Medical field will be discussed in these topics. One of the advantages of the laparoscopy that of obtaining a virtually micro-surgical view compared to that obtained by laparotomy. Whereas in fact at present, this view has become Opto-electronics. Quality of the image obtained very much depends on the quantity of light available at each step of the optical and electronic system.
A typical light source is consist of
- A lamp
- A heat filter
- A condensing lens and
- Manual or automatic intensity control circuit.
Lamp:
Lamp or bulb, the most important part of the light source. The Quality of light depends on the lamp used. Several Modern types of light sources are currently available on the market. These light sources mainly differ in the type of bulb used. Four types of lamps used more recently.
- Quartz halogen.
- Incandescent bulbs.
- Xenon & halogen
- Metal halite vapor arc lamp.
Halogen bulbs
Halogen bulbs provide a highly efficient, almost crisp white light source with excellent color rendering. Electrodes in halogen lamps made of tungsten; this is the only metal with a sufficiently high melting temperature and sufficient vapor pressure at elevated temperatures. They use a halogen gas that allows bulbs to burn more intensely without sacrificing life. Halogen bulbs are low voltage and have an average life of 2,000 hours.
The color temperature of the Halogen lamp is (5000-5600 K). These lamps available cheaply and used for laparoscopic surgery if a low budget setup.
Xenon lamps
Xenon lamps consist of a spherical or ellipsoidal envelope made of quartz glass, which can withstand high thermal loads and high internal pressure. For ultimate image quality, only the highest-grade clear fused silica quartz. Typically doped, although not visible to the human eye. It absorbs harmful UV radiation generated during operation. The color temperature of the Xenon lamp is 6000-6400 K.
The operating pressures are tens of atmospheres at times, with surface temperatures exceeding 600 degrees C.
Notes
The lifespan of the lamp must be noted down and labeled it on the lamp control panel for the remembrance of changing. The alternate bulb must be kept ready for the emergency situation by the storekeeper or sister in charge.