Bushnell®
Night Vision monoculars, binoculars and goggles amplify existing light,
allowing you to see in conditions too dark for the naked eye. An infrared
illuminator is available on all Bushnell Night Vision devices for use in
caves, warehouses or other locations where there is no ambient light to
amplify.
How to Choose
Choose a device with range and image quality suited to your application. Other
factors to consider are size, weight and ease of use.
Intended Use
|
Recommended Models
|
|
Close-Range Viewing (Security)
|
1.7x29, 2.0x42, 2.4x29 Monoculars, 1.0x20 Goggle, 3.1x50 Binocular |
Long-Range Viewing
(Wildlife Observation)
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3.6x52, 2.0x42, 4.3x66 Monoculars, 3.1x50 Binocular |
|
Fishing & Boating
|
2.0x42, 2.4x29 Monocular, 3.1x50 Binocular |
| How Does It Work? |
- Available light (energy) is collected by the objective lens and
focused on the image intensifier.
- Inside the intensifier, a photocathode is "excited"
by the light and converts the energy into electrons.
- The electrons accelerate across an electrostatic field inside
the intensifier and strike a phosphor screen (like a monochrome
TV screen) which emits an image that you can see. This acceleration
of electrons provides gain and enhances the image
|
Terminology
Angle or Field of View
The measure of the angle defining the field visible through the Night Vision
system at a distance of 100 yards.
Bright Source or Over-Light Protection
An electronic circuit that turns the power to the Night Vision device down or
off when it is exposed to bright light (such as automobile headlights). This
protects the image intensifier and extends its life. The device will recover
and resume normal operation in 1-2 minutes.
Eyepiece Focus
Used to match your Night Vision scope or binocular to your specific eyesight.
Image Intensifier or Intensifier Tube
The active component in a Night Vision System that amplifies light and presents
a usable image.
Infrared (IR) Illuminator
Provides a light source for the system to amplify, yielding enhanced images
in very low light conditions such as caves where no ambient light is available
for amplification.
Night Vision Binocular
Two complete sets of optics and image intensifiers that are connected together
and share a common power supply.
Night Vision Monocular
A Night Vision device for use with one eye.
Objective Lens
Collects all available light and focuses it on the image intensifier. It also
provides image magnification. The best objective lenses have low magnification
(5x or less), are high-speed (f2 or faster) and are coated for maximum efficiency
in the near-infrared bandwidth.
Phosphor Screen
Positioned at the back of the intensifier tube, the green phosphor screen renders
a visible night vision image. The human eye is most sensitive to green contrasts.
Photocathode
Converts light (photon energy) into electrons (electrical energy) which are
then amplified in the intensifier. The objective lens focuses available light
on the photoelectric surface of the photocathode, which is excited and passes
electrons within the tube.
Resolution
A measure of the ability to render and display a detailed image. Image intensifier
resolution remains constant and is expressed as the maximum number of line pairs
per millimeter (lp/mm) that can be discerned when a black-and-white stripe pattern
is focused on the photocathode.
