Optical techniques are methods that use light to probe or control matter. One prominent example is optical spectroscopy, which includes such methods as pump–probe spectroscopy, Raman spectroscopy and ...

Biological techniques are methods or procedures that are used to study living things. They include experimental and computational methods, approaches, protocols and tools for biological research.

A simple, low cost, and precision frequency meter uses only two pins of a pc parallel port (Figure 1). The TTL-level periodic input signal with frequency f IN connects to the ACK pin of LPT1. This ...