The LI15 Fizeau Interferometer is useful where data acquisition is required to help speed up the assessment process. 
Key Features
- High precision flatness measurement of polished samples to lambda/10
- 3 dimensional imaging & analysis capacity
- Measure 0.335µm per fringe with high clarity
- Image & analyse fringe patterns on materials from 1" to 6"ø
Description
The Logitech LI10 is a multiple beam fizeau interferometer ideally suited to a wide range of flatness measurement operations on specimens up to 102mm (4") diameter in both optical component production and research and development laboratories.
Our fizeau interfometers offer a rapid and accurate method for the optical measurement of surface flatness and has the distinct advantage of non-contact between the reference flat, which has a flatness of l/20, and the surface under test. Operating on the principle of optical interference, where fringes are caused by the interference of reflections between the two surfaces with an air space in between, the unit produces a contour map, or interferogram.
The LI10 fizeau interferometer is a manual unit and allows the resulting interferogram to be viewed through either a wide angle telescope (supplied as standard) or binocular viewer (ideal for prolonged viewing or spectacle wearers).
Using the LI10 fizeau interferometer, the fringe patterms are easily envisaged as altitude contours. Each fringe represents a 0.316µm change of spacing in the air gap between the specimen and the reference flat.
Convexity and concavity are determinded by gentle finger pressure as if to close the air gap. Fringes on the interferometer always move away from the point of minimum air gap (i.e. area of roundness) and conversely towards the maximum air gap (i.e. the area of hollowness). As interferometry determines any departure from specimen flatness and requires some degree of tilt between specimen and reference flat to do this, it is necessary to compensate for any residual net tilt by visually minimizing the fringe count. As a result, using the LI10 fizeau interferometer ensures that the flatness measurement is as accurate as possible.
Fizeau Interferometer Applications
The Logitech LI10 fizeau interferometer is ideal for checking optical flats and for carrying out flatness measurements on a wide range of optical components. It can be used for measuring the flatness of polished semiconductor or optical materials, where flatness is essential for subsequent processing.
Product Options
The LI10 fizeau interferometer is available in either 220V, 50Hz or 110V,50Hz and is available with the following additional accessories :
- Vacuum Chuck
- Wide Angle Telescope
- Binocular Viewer
- Polaroid Camera
- CCTV 220V/50Hz
Product Specification
| Power Supply : | 240V, 50/60Hz 110V, 50/60Hz |
| Max Sample Size : | 102mm (4")ø (5"/6" on other models) |
| Aperature : | 102mm (4")ø (5"/6" on other models) |
| Refernce Flat : | Flatness  /10Parallelism 20 +/- 5 min of arc min. positive wedge |
| Fringe Spacing : | 0.316µm |
| Illumination : | 0.5mw HeNe Laser |
| Height : | 315mm |
| Depth : | 320mm |
| Width : | 215mm |
| Net Weight : | 7.6Kg |
For more information on the LI10 Fizeau Interferometer, call us on +44 (0)1389 875444 or complete our contact form.