one of a group of cells that develop in the walls of the seminiferous tubules. Spermatogenic cells include spermatogonia, spermatocytes, and spermatidsâall of which are transitional forms between primary sexual cells and spermatozoa.
long-haul optics. Long-haul optics refers to the transmission of visible light signals over optical fiber cable for great distances, especially without or with minimal use of repeaters. Normally, repeaters are necessary at intervals in a length of fiber optic cable to keep the signal quality from deteriorating to the point of non-usability. In long-haul optical systems, the goal is to minimize the number of repeaters per unit distance, and ideally, to render repeaters unnecessary.
Single mode fibre is optical fibre that is designed to carry a single signal at a time. It is used mainly for long distance signal transmission. A: STEP-INDEX MULTIMODE FIBRE has a large core, up to 100 microns in diameter. As a result, some of the light rays that make up the digital pulse may travel a direct route, whereas others zigzag as they bounce off the cladding.