etalon

A spectroscopic instrument used to measure and control optical wavelengths. Also known as an

interferometer, an etalon comprises two parallel reflecting plane surfaces. Etalons are widely used in lasers.

See also Fabry-Perot laser.

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• PSQM (Perceptual Speech Quality Measurement)
• PSQM+ (Perceptual Speech Quality Measurement plus)
• PSS1 (Private Signaling System No. 1)
• PSTN (Public Switched Telephone Network)
• PSTS (Public Switched Telephone System)
• PTE (Path Terminating Equipment)
• PTI (Payload Type Indicator)
• PTT
• PTT
• public data network (PDN)
• public domain
• public IP address
• public key encryption
• public key infrastructure (PKI)
• Public Safety Access Point (PSAP)
• Public Service Commission (PSC)
• public switched telephone network (PSTN)
• public switched telephone system (PSTS)
• Public UNI (Public User Network Interface)
• Public Utility Commission (PUC)
• PUC (Public Utility Commission)
• pull
• pulse
• pulse amplitude modulation (PAM)
• pulse code modulation (PCM)