Night Optics and Observation Flashcards
What are the two types of Passive Night Sights?
- Thermals
- Ambient light NVDs
What are the 4 types of Ambient Light NVDs?
Generation I, II, III, and IV
Which type of Ambient Light NVDs is best for MOUT?
Generation II+
Generation IV is referred to as what?
“Filmless and gated image intensifiers”
What are the Night Aiming Devices?
The Advanced Target Pointer Illuminator Aiming Light (ATPIAL) or PEQ-15
The PEQ-15 is classified as what kind of laser device?
Class 3b
What weapon systems can the PEQ-15 be mounted on?
M4/M16-A4, M249, M240, M2, and Mk19
NVGs can “see” what ranges in the spectrum?
Visible light, near IR, mid IR, and far IR (near, mid, and far IR are also the “thermal” spectrum)
What is the field of view with NVGs?
40 degrees (the human eye is about 170)
NVGs give you what clarity?
20/25 - 20/40 at best, with optimal illumination and contrast
NVG users tend to _________ distance and ___________ depth.
overestimate; underestimate (how tall an object is)
Why are NVGs green?
The human eye can detect the most differentiating shades in green.
What is moonrise?
When the upper edge of the moon’s disk is coincident with the horizon in the east.
What is moonset?
When the upper edge of the moon’s disk is coincident with the horizon in the west.
What is twilight?
When the upper atmosphere receives direct sunlight and reflects it back to the Earth’s surface to provide natural light.
What are the three types of twilight?
Civil, Nautical, and Astronomical
What is Civil Twilight?
When the center of the sun is 6 degrees below the horizon. The brightest stars and planets can be seen. (Begins in the morning and ends in the evening).
What is Nautical Twilight?
When the center of the sun is 12 degrees below the horizon. Enough light is available to identify the general outline of ground objects. (Begins in the morning and ends in the evening).
What is Astronomical Twilight?
When the center of the sun is 18 degrees below the horizon. The sun does not contribute to sky illumination. (Begins in the morning and ends in the evening).
The PVS-14s are what type of Ambient Light NVDs?
Generation III
What is the range of PVS-14s?
150m (starlight)
300m (moonlight)
On the PVS-14s, a blinking red dot in eyepiece signifies what?
Less than 30 minutes of battery life.
What are the four adjustments of the PVS-14s?
- Variable gain (brightness)
- Objective lens focus (sharpness of viewed image)
- Diopeter adjustment ring (sharpness of intensifier screen)
- Eye relief
What is the range of thermal sights?
Human can be detected at > 3km.
Human can be recognized at > 1km.
Vehicle/tank can be detected at > 8km.
Vehicle/tank can be recognized at > 2.3km
What is the range of the laser on the PEQ-15s?
25m
What is the range of the IR laser on the PEQ-15s?
> 600m (low), > 2000m (high)
What is the range of the IR illuminator?
> 2000m
