principal plane

American  

noun

Optics.

1. a plane that is perpendicular to the axis of a lens, mirror, or other optical system and at which rays diverging from a focal point are deviated parallel to the axis or at which rays parallel to the axis are deviated to converge to a focal point.

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Example Sentences

Consider other relief options first: Interest will accumulate during these pauses, and it will be added to your principal loan balance once payments restart.

From Seattle Times • Apr. 20, 2023

The actual mortgage — excluding repayment of the principal loan amount — contributes about 30 percent to the total costs over that seven-year period.

From New York Times • May 1, 2022

For the typical Fortress product, a retail investor puts up a principal loan amount of between C$30,000 and C$100,000 for two to five years.

From Reuters • Nov. 30, 2017

For the typical Fortress product, a retail investor puts up a principal loan amount of between C$30,000 and C$100,000 for two to five years.

From Reuters • Nov. 30, 2017

The insurance premium that buyers pay in addition to their monthly mortgage payment traditionally expires once 22 percent of the principal loan is paid — usually in the first few years of a mortgage.

From Washington Post • Jun. 5, 2013