It is preferable to use a cardioid condenser rather than a paraboloid condenser for darkfield fluorescent microscopy.
The microphones are typically cardioid or super cardioid microphones and therefore the best quality signal for each speaker.
Slightly higher power levels may be allowed in certain cases when cardioid antennas are utilized.
The cardioid, for instance, features a partially closed backside.
cardioid subwoofer prediction software examples with charts and photos.
British Dictionary definitions for cardioid
a heart-shaped curve generated by a fixed point on a circle as it rolls around another fixed circle of equal radius, a. Equation: r = a(1 – cos φ), where r is the radius vector and φ is the polar angle