WAT TUNNELAN AFFORDABLE:

POLARIZATION DETECTOR, RESOLVER, BEAM SPLITTER,

AND LINEAR QUADRATURE DETECTOR

JANUARY 2015

An improved polarizing

beam-splitter/detector

combination. Arranged as a

pair for detecting state of

polarization of a light beam.

Compact size: 33 mm (1.3”)

long, 10 mm (.4”) high.

Part of the original beam is

preserved.

The TUNNEL comes with

integrated detectors but is also

available without detectors or

with custom detectors.

Integral amplifier with greater

than 1 MHz bandwidth.

The sketch illustrates the

separation of a light beam

into s and p polarizations by

Fresnel Reflection at an

interface with a material

having a different index of

refraction.

A slab of material is placed

at Brewster’s Angle with

respect to the incoming

beam.

The reflected beam (s) is

entirely of one polarization

while the transmitted beam

(p) contains all polarizations.

Principle of Operation

Reflected beams are

directed at electronic

Sensors detecting the

intensity of the beams

The first two slabs, S1 and S2, are

arranged at 90° with respect to each

other so that the sensors, D1 and D2, can

be mounted flat on the same PC Board.

Incoming light is resolved

into an electronic signal

according to its orthogonal

states of polarization

Construction Details of the WAT TUNNEL

Typical TUNNEL Output for Polarized Infrared VCSEL Emitter

Typical Extinction Ratio Response Averages: Over 50 to 100

Possible applications of the TUNNEL. Above, in

an interferometer using the TUNNEL to resolve

quadrature signals, and measure the position

of a translating or vibrating mirror. Side, as a

Rotation Angle Sensor.

For more information, contact:

tunnel_sales@watinc.biz

Or call:

David Wright at 802 685 2152