Interferometer
Instrument to check flatness of the Optical components by various Optical manufacturing industry.
Fizeau Interferometer
Interferometers are essential measurement tools for the production and quality control of optical components and systems. Their applications range from testing the flatness and sphericity of surfaces to measuring radii and testing the performance of optical systems.
- Technical mass products with flat surfaces specified to better than 0.1µm over a few cm are produced by millions per month.
- The production processes are lapping & polishing – and, increasingly more often, micro-machining; 90% have diameters under 50mm.
- ISO 9000 requires tight inspection often 100%.
- The most common tool for this is The Interferometer
- An esteemed value to engineers as does the stethoscope for the medical practitioner.
Specifications
| Measurement | Measures radius of Curvature for Spherical Surfaces |
| Capability | Transmitted wavefront of transparent spherical optics |
| Transmission Flat Accuracy | λ/.10 & λ/.20 |
| Reference Flat Mounting | Bayonet Mounted |
| Clear aperture | Ø 60 and Ø 100 mm |
| Fringe Analysis Software | Static Fringe |
| Zoom Control | Wired |
| Optical Zoom | 6X |
| Alignment field of view | +/- 2 degrees |
| Dimensions | 470 x 500 x 1230 mm |
| Weight | <90 Kgs |
| Power Input | 220 V AC, 50 Hz |
Michelson Interferometer
The Michelson interferometer is an optical instrument of high precision and versatility. It generally is used in investigations that involve small changes in optical path lengths. With the Michelson interferometer, one can produce circular and straight-line fringes of both monochromatic light and white light. One can use these fringes to make an accurate comparison of wavelengths, measure the refractive index of gases and transparent solids, and determine small changes in length quite precisely. The instrument can be used as a stable mode selecting resonator element in laser cavities as well. The Michelson interferometer is perhaps the best known and most basic in a family of interferometers which includes the Fabry-Perot interferometer, the Twyman-Green interferometer and the Mach-Zehnder interferometer
The Plano Optics make Michelson Interferometer is constructed on a Machined Steel Base. High precision movable-mirror with smooth fine movement of 0.6 microns facilitates fringe counting.
You can upgrade by adding few parts to work as Fabry Perot Interferometer & Twyman Green Interferometer.
Michelson Interferometer
Interference Fringes Observation
- Study of Equal Inclination, Equal Thickness & White Light Interference Fringes
- Measurement of Wavelength of the Sodium D-lines
- Measurement of the Wavelength Separation of Sodium D-lines
- Study of Refractive Index of gases at varying pressure
- The Refractive Index of Transparency Slice
Fabry-Perot Interferometer
The Multi-beam Interference
- Measurement of the Wavelength of He-Ne Laser
- Observation of the Interference of Sodium D-lines
Twyman-Green Interferometer
Demonstration of the principle of Twyman-Green interferometer
- Checking Principle of defects in Optical Components.(Flat Mirrors, Windows, Prism & Lenses
Model PIM # Precision Interferometer parts:
P-IM-01: Instrument Base
P-IM-02: Mirror with Kinematic tilt and linear movement by micrometre
P-IM-03: Adjustable Mirror with Kinematic tilt
P-IM-04: Beamsplitter & Compensator Assembly
P-IM-06: Viewing Telescope
P-IM-06: Pin Hole Screen / Collimator with kinematic tilt
P-IM-07: Diffuser glass with mount
P-IM-08: Kinematic Laser Diode Mount (12 mm dia)
P-IM-09: Equilateral prism and holding table
P-IM-10: Air Chamber with Pressure Gauge
P-IM-11: Fabry Perot Etalon Assembly with Kinematic tilt
P-IM-12: Laser Diode 3 mW with power supply.
P-IM-13: He-Ne Laser 1 mW with power supply.
P-IM-14: Sodium Vapour Lamp 35 watts with power supply.
P-IM-15: Rotating Slice.
P-IM-16: Laser Beam Expander Lens
P-IM-17: He-ne Laser Mount
Parts Description
Model: MIM # Michelson Interferometer parts: P-IM-01 to 07
Special Features:
- Optics: 25 mm diameter (Clear Aperture:20mm), Flatness to »/6 @ 633nm.
- P-IM-02 Kinematic Mirror with Linear movement: One division of the micrometre (0.01mm) corresponds to 0.6 ¼ movement of the Mirror.
- P-IM-03 Adjustable Mirror: Coarse Linear travel of 5 mm and movement.
Gracing Incidence Interferometer for Flatness Measurement of Non Reflective or Reflective surface
- The principle of measurement is based on interferometry by grazing incidence.
- Flatness measurements of polished as well as non-reflective, rougher surfaces
- Flat Surfaces that is not measurable with traditional interferometers.
- An air gap between prism and part ensures no physical damage of the part to be inspected.
- The sensitivity can be selected from four calibrated settings. (0.5, 1, 2, and 4um/fringe)
- Visual evaluation of light bands on a Monitor/Computer
- Quick inspection of lapped parts with specially designed platform that could be pulled and pushed by replacing the test part.
- Measurement can be saved and thus be evaluated and printed out at a later time.
Specifications
| Repeatability | better than 0.03 μm |
| Resolution | 0.03 μm |
| Accuracy | 0.1-0.4 μm+ 2% of the measured value |
| Calibrated Sensitivities | 0.5, 1.0, 2.0 & 4.0 μm per fringe |
| Flatness of Reference surface of Prism | 0.06 μm |
| Dynamic Range | > 100 μm |
| Part Range | 50 mm - 100 mm |
| Measurement Time | 5 seconds (typical) |
| Surfaces | Ground, lapped or polished |
| Interferometer Housing | 65 cm x 65 cm x 35 cm |
| Weight | < 40 kg |