Glossary - alphabet order - "H"
Half wave plate
It gives a light path difference of a half wavelength (phase difference δ = 180° + N × 360°, N is an integer ) to two linearly polarized light (parallel and perpendicular light components) when light passes through the half-waveplate. It rotates the plane of polarization by the required angle.
Hermetic seal
A hermetic seal is part of a metal can package that allows a lead (pin) to protrude from the package while maintaining the vacuum condition and insulation of the output signal.
Structure diagram of crystal unit
High frequency
The high frequency band is in the megahertz (MHz) section of the frequency spectrum.
Reference: Frequency band
Hz
This is the symbol for Hertz, a unit of measure for frequency. 103 Hz = 1 kHz (kilohertz), 106 Hz = 1 MHz (megahertz), and 109 Hz = 1 GHz (gigahertz).