White light interferometer

T. Bosselmann and T. Ulrich, High accuracy position sensing with fibre coupled white light interferometers, Proc. of2ndConf. on Optical Fibre Sensors (OFS 84). SPIE Proc. 514, 361 (1984). 

Indentation hardness determinations were performed in dynamic mode ( 1500 mm/sec impact speed) using a pendulum impact device and in quasistatic mode ( 0.008 mm/sec impact speed) with a custom-built indentation tester. The spherical indenters were of 2.54 cm diameter and 65.6 g mass, and the pendulum length was 92.3 cm with a release angle of 30°. Quasistatic indentation forces were selected to produce indentations of a similar size to the dynamic indentation test (1.5 to 2.0 mm radius). The compact indentations were measured using a white light interferometer (Zygo Corporation, Middlefield, Connecticut, U.S.A.) and the dent depth, dent diameter, apparent radius of curvature, and pendulum initial and rebound heights were used to calculate the indentation hardness of the compacts. 

FIGURE 16-4 inierferometers in an FTIR spectrometer. Subscript 1 defines the radiation path in the IR interferometer, Subscripts 2 and 3 refer to the laser and white-light interferometers, respectively. (Courtesy of Thermo Electron Corp., Franklin. MA.)... 

M.R. Viotti, A. Albertazzi, A.V. Fantin, A. Dal Pont. Comparison between a white-light interferometer and a tactile form tester for the measurement of long inner cylindrical surfaces, Optics and Lasers Engineering, 46 (2008), pp. 396-403. 

Pati GS, Salit M, Salit K and et al. Demonstration of a tunable-bandwidth white-light interferometer using anomalous dispersion in atomic vapor. Physical Review Letters 2007 Sep 27 99(13) 133601(4). 

With modern measurement devices, as shown Figure 4.113 on the left (white light interferometer sensor for sensing of surface roughness or grains), the grain can also be scanned and evaluated on a surface. Different results can be generated with this data. In addition to the above-mentioned measured values, the surface value,... 

Figure 7.2 A white light interferometer can be used to make measurements of the device under test without contacting it. This technique is most often used to obtain height information for MEMS structures. It can be usefiil to measure out-of-plane displacement information for vertical actuators.

Three-dimensional profilometry pictures of hybrid coatings were obtained with a Wyko NT3300 white light interferometer (Veeco Company). Further topography data treatment was performed using Mountains Map software (Digital Surf Company). 

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