Introduction to Infrared and Electro-Optical Systems
RF Cafe Quiz #48

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Introduction to Infrared and Electro-Optical Systems - RF CafeThis quiz is based on the information presented in "Introduction to Infrared and Electro-Optical Systems," by Ronald G. Driggers and Melvin H. Friedman.

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1.  What is the term for light distribution on the image plane from a point source?

a)  Point spread function
b)  Light distribution function
c)  Specular distribution function
d)  Snell's Law

2.  What is the term for when there is a fixed phase relationship of an EM field between two points in space or two points in time?

a)  Commonality
b)  Planar
c)  Incoherence
d)  Coherence

3.  What is the term describing "any deviation of light rays from rectilinear paths which cannot be interpreted as reflection or refraction?"

a)  Reflection
b)  Refraction
c)  Diffraction
d)  Specular addition

4.  Which material listed below has the highest total emissivity (defined as total spectral signature wrt a blackbody)?

a)  Snow & graphite
b)  Paper & brick
c)  Polished gold & polished brass
d)  Oxidized brass & oxidized steel

Optical Lens Ray Tracing - RF Cafe5.  Match the lens ray tracing diagram with its application type.

a)  Magnifying glass ____
b)  Telescope          ____
c)  Camera             ____
d)  Search light       ____

6.  What is a 'Cold Shield' as used in electro-optical systems?

a)  A military acronym for special night combat exercises
b)  A cooled aperture adjacent to the detector plane
c)  Super-cooled armor placed around an infrared system
d)  The cold calibration standard used in conjunction with a "hot" standard

7.  What are the two general classes of electro-photonic detectors?

a)  Electronic and photonic
b)  Photon (quantum) and thermal
c)  Up and down spin
d)  Commercial and military

8.  What is a bolometer?

a)  A device for generating a broadband noise spectrum
b)  A device for generating a narrowband noise spectrum
c)  A device for measuring the inverse resistance of light
d)  A device which varies its electrical resistance depending on the total electromagnetic power incident upon it.

9.  What is the modern name of the U.S. Army's former Night Vision Laboratory (NVL)?

a)  Post-Day Vision Laboratory (PDVL)
b)  Night Vision & Electronic Sensors Directorate (NVESD)
c)  Robert C. Byrd Night Vision Laboratory (RCBNVL)

b)  Night Vision & Electronic Sensors Directorate (NVESD)

The [infrared] effort began approximately 50 years ago at the then U.S. Army Night Vision Laboratory (NVL). Today NVL is known as the U.S. Army Communications & Electronics Command (CECOM), but is still referred to as NVL in the community and that acronym.  (see page 373)

10.  What is Persistent Surveillance?

a)  The use of wide-area coverage airborne sensors
b)  Long-term surveillance
c)  Unyielding surveillance
d)  Narrowly focused surveillance

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