catastrophic laser-damage threshold
灾变

• peep sight
• peep-sight alidade
• peformance margin
• pellet
• pellet corona
• pellet electrode
• pellicle
• pellicle mirror
• pellicle reflector
• Pellin-Broca monochromator
• Pellin-Broca prsim
• pellucid
• pellucidity
• Peltier coefficient
• Peltier constant
• Peltier effect
• Peltier's element
• Peltier's heat
• penality function
• pencil
• pencil-beam light
• pencil-beam pattern
• pencil of rays
• pencil test
• pendant control