The Workshop Autocollimator

The Angle Dekkor is a compact, versatile autocollimator for general workshop use in checking angles and small displacements. It is easy to set up and produces an image of high contrast, even from surfaces of low reflectivity. It provides simultaneous measurement in two planes from an eyepiece graticule.

The Autocollimator is used as an angle comparator to check or measure:

• Angles of Prisms and other glass components
• Parallelism of glass plates
• Definition of flat surfaces

Focometer

The Focometer is designed to determine the focal length of single and combined positive lenses up to 1000 mm and negative lenses up to 1000 mm, as well as the free aperture.

The clear aperture of the Collimator Objective is 60 mm. The collimator objective is corrected fulfilling the Raylleigh Criterion.

Collimator No. 2MK-II

It is a highly optimized collimator used for optimization of Optical Instruments with high accuracy. Basically used for measuring Field of View and the definition of the Instruments which are used for viewing objects at infinity.

Specification
Diametre of OG : 60mm
Focal Length : 300mm

Test Charts

Definition Chart is available for checking the definitions and the field of view of the optical instruments. The graduations are made upto 2 deg. with the least count of graduation 5 min.

USAF Resolving Power Test Targets are available in two patterns, 0-7 and -2-7. The most popular range is 0-7 group, with 6 elements per group, an element consisting of two target patterns of 3 lines at 90º to each other, the line space ratio being equal. These charts are produced as a chrome surface image on glass plate.

Definition Charts and Test Resolution Charts are normally supplied as chrome high contrast pattern with positive image. Can be supplied in low contrast and negative form on request. Range from 3 lines to 20 lines per mm. Star Test Target is used qualitatively to demonstrate focusing affects and for rapid assessment of focal plane position. Its overall size allows it to be used not only as a camera or optical bench target, but also as a test slide for 35mm projectors.

A Collimator is an instrument that projects the image of a reticle to a certain distance or to infinity. Usually the image is at infinity at visible wavelength.

The main components of a collimator are:

• Objective Tube with Objective Lens
• Reticle sleeve with Reticle.
• Illumination (Optional)

The reticle is positioned at the front focal length of the objective. Due to this configuration all light beams passing a point in the reticle plane form a parallel light behind the objective.

There is no real image of the reticel. However to obtain a real image, an additional objective of a telescope is required.

Collimator with Infinity Setting
A collimator in an instrument that projects the image of a reticle to infinity. Consequently a bundle of parallel light emerges from the collimator.

Collimator with Tube Extension
Collimators with tube extension are used if a variable distance setting (Finite and infinite) is required. With the help of the tube extension the position of the reticle in respect to the focal plane of the objective is changeable. As a result of that the former parallel beam converts into a convergent or divergent beam and yields a real or virtual image of the reticle.

Tube Collimator

This is a mirror type collimator having a parabolic mirror for high resolution. The collimator is constructed in aluminum tube, with matt black internal walls and is mounted on iron stand and aligned in our laboratory. To facilitate ease of use, the collimator is adjustable by foot screws for center height adjustment.

• Mirror is concave parabolic with effective focal length 1000mm and clear aperture of 200 mm
• irror coating is of gold for high reflectance in Near IR and IR regions (96% reflectivity from 750nm to 1500nm). Gold coating is protected by protective overcoat for durability and necessary handling purpose.
• Three, foot screws are provided for height adjustment.

Spirit Level is a tool for determining whether a surface is horizontal. The plumb line was used to determine vertical position from ancient times until the 19th century. At that time the spirit level, which was invented in France during the 17th cent., came into general use and replaced the plumb line in some applications.

Specifications:

Size: 10mm – 100mm
Diamtere of glass tube: 4mm – 12mm
Sincitivity: 10 arc sec. – 30 min.

Dioptric Telescope

+ 1.5 Diopter

Hind - Opt Dioptric Telescope is a very Handy Instrument, which enables convenient usage of range + 1.5 D, graduated at intervals of 0.25 D. The mean average accuracy of the instrument is + 0.125 Diopters. The internal surfaces of the lenses are bloomed with AR coating to provide better resolution and enhance image sharpness. The eye piece of the Dioptric Telescope is Individually focusing type to suit the observer’s eye and to remove the parallax against the graticule provided in the focal plane.

Leakometer

This equipment is used for measuring the rate of leakage in sealed optical instruments.

The apparatus consists of a low-pressure pump, a desiccator air chamber, and a measuring head for measuring the rate of leakage.

Auxillary Telescope

Specifications:

• Focal Length of OG: app. 3 inches
• Eye Piece: 10x magnification
• Reticle: Cross Line

Dynameter

Besides the modular designed testing telescopes and collimators, Dynameter Microscope for testing of other Parameters in the Optical Workshop.

Dynameter is mainly used for the measurement of:

• Magnification of optical instruments
• Diameter of exit pupil
• Distance between exit pupil and eyepiece