Carousel Interferometer for Metrological Applications Ghazanfar Hussain Sensors

Carousel Interferometer for Metrological Applications Ghazanfar Hussain (Sensors Group, NILOP) National Institute of Lasers and Optronics 10/31/2020 1

Carousel Interferometer for Metrological Applications Mirror Beamsplitter LASER 10/31/2020 Mirror Interference Fringes 2

Carousel Interferometer for Metrological Applications Prism Interference Fringes Prism LASER Beamsplitter Interference Fringes 10/31/2020 National Institute of Lasers and Optronics, Islamabad 3

Carousel Interferometer for Metrological Applications Metrology - Backbone of Manufacturing and Services Industries and hence Economy of a Country Metrology of Optical and Mechanical Components and Systems Dimensional Metrology Thickness and Length Measurements Angle Measurement Axis of Rotation Simultaneous Measurement of Angle and Axis of Rotation and Slip Calibration of Gyroscopes and the Wheels Vibration Detection Calibration of Optical Sources Optical Surface Characterization Many Others 10/31/2020 National Institute of Lasers and Optronics, Islamabad 4

Carousel Interferometer for Metrological Applications Carousel Interferometer Two Right-angle Prism & Compensator Glass Plate Assembly Rotation introduce Individual and Relative Optical Path Differences (OPDs) in the two Arms One and Three Outputs in different Setups Determines Angle and Axis of Rotation Error in retrieved Angle and Axis of Rotation is in the Range 10/31/2020 5

Carousel Interferometer for Metrological Applications 10/31/2020 National Institute of Lasers and Optronics 6

1 March 2010 / Vol. 49, No. 7 / APPLIED OPTICS 10/31/2020 National Institute of Lasers and Optronics 7

Carousel Interferometer for Metrological Applications 10/31/2020 National Institute of Lasers and Optronics 8

Carousel Interferometer for Metrological Applications 10/31/2020 Carousel Interferometer and it Metrological National Institute of Lasers and Optronics Applications 9

Carousel Interferometer for Metrological Applications 10/31/2020 National Institute of Lasers and Optronics 10

Carousel Interferometer for Metrological Applications 10/31/2020 National Institute of Lasers and Optronics 11

Carousel Interferometer for Metrological Applications 10/31/2020 National Institute of Lasers and Optronics 12

Carousel Interferometer for Metrological Applications 10/31/2020 Carousel Interferometer and it Metrological National Institute of Lasers and Optronics Applications 13

Carousel Interferometer for Metrological Applications 10/31/2020 National Institute of Lasers and Optronics 14

Carousel Interferometer for Metrological Applications Optimized Parameters and Given Values Given Parameters λ = 632. 8 nm no = 1. 00000 ns = 1. 84489 ψ = 15. 5° to 15. 6° α = 0° to 360° R 1 =1000. 2002 mm Optimized Parameters Δxo = 7. 4423 mm Δyo = 0. 0000 mm do = 39. 9544 mm 10/31/2020 National Institute of Lasers and Optronics 15

Precision Measurement of Angle and Axis of Rotation 10/31/2020 National Institute of Lasers and Optronics 16

Precision Measurement of Angle and Axis of Rotation 10/31/2020 National Institute of Lasers and Optronics 17

Precision Measurement of Angle and Axis of Rotation 10/31/2020 National Institute of Lasers and Optronics 18

Precision Measurement of Angle and Axis of Rotation Radius of Rotation and Error Quantity Actual Radius =1000. 2002 mm -15 o -10 o -5 o 0 o 5 o 10 o 15 o Radius (1. 0 e+003 ×) Millimeter 1. 00020026366540 1. 00020024540706 1. 00020019595567 Na. N 1. 00020019279368 1. 00020025472719 1. 00020026491085 Error in Radius (1. 0 e-004×) Millimeter -0. 63665399920865 -0. 45407055836222 0. 04044328534292 Na. N 0. 07206319082798 -0. 54727186579839 -0. 64910854234768 10/31/2020 National Institute of Lasers and Optronics 19

Carousel Interferometer for Metrological Applications Parallel Plate Carousel Interferometer (OPTICS LETTERS / Vol. 29, No. 16 / August 15, 2004) • Compact • Rugged • Inherently Nonlinear • Optimization for Linearity 10/31/2020 Carousel Interferometer and it Metrological National Institute of Lasers and Optronics Applications 22

Carousel Interferometer for Metrological Applications 10/31/2020 Carousel Interferometer and it Metrological National Institute of Lasers and Optronics Applications 23

Carousel Interferometer for Metrological Applications 10/31/2020 National Institute of Lasers and Optronics 24

Carousel Interferometer for Metrological Applications Error from a straight line after optimizing the glass plate thickness. 10/31/2020 National Institute of Lasers and Optronics 25

Carousel Interferometer for Metrological Applications 2β θr a 3 a 2 2β M 4 M 3 M 2 a 1 θ 2 GP 1 y M 1 x O(x, y) θ 1 a 4 Detection after Interference M 5 10/31/2020 BS α α a 5 Incident Beam M 6 National Institute of Lasers and Optronics 26

Carousel Interferometer for Metrological Applications Given Parameters λ a 1 a 3 a 1 a 5 10/31/2020 632. 8 х10 -6 mm 200 mm 160 mm ns 1. 84489 θ 1 45ᴼ θ 2 110ᴼ α 80ᴼ 27

Carousel Interferometer for Metrological Applications 10/31/2020 National Institute of Lasers and Optronics 28

Carousel Interferometer for Metrological Applications 10/31/2020 National Institute of Lasers and Optronics 29

Carousel Interferometer for Metrological Applications 10/31/2020 National Institute of Lasers and Optronics 30

Carousel Interferometer for Metrological Applications 10/31/2020 National Institute of Lasers and Optronics 31

Carousel Interferometer for Metrological Applications Figure 3. Plot of residual OPD at optimized value without glass plates as a function of angle of rotation; a, b, c, & d represent rotation ranges of ± 5ᴼ, ± 10ᴼ, ± 15ᴼ, and ± 20ᴼ respectively. 10/31/2020 National Institute of Lasers and Optronics 32

Carousel Interferometer for Metrological Applications Figure 4. Plot of residual OPD at optimized value with glass plate as a function of angle of rotation; a, b, c, & d represent rotation ranges of ± 5ᴼ, ± 10ᴼ, ± 15ᴼ, and ± 20ᴼ respectively. 10/31/2020 National Institute of Lasers and Optronics 33

Carousel Interferometer for Metrological Applications Range of rotation 10/31/2020 Maximum residual OPD (fringes) Maximum nonlinearity Without glass plates With glass plates -5ᴼ to +5ᴼ 37 0. 018 7. 7 х10 -4 5. 40 х10 -7 -10ᴼ to +10ᴼ 295 0. 58 6. 20 х10 -3 8. 53 х10 -6 -15ᴼ to +15ᴼ 991 4. 20 7. 02 х10 -3 4. 18 х10 -5 -20ᴼto +20ᴼ 2335 16. 56 1. 25 х10 -2 1. 26 х10 -4 National Institute of Lasers and Optronics 34

Carousel Interferometer for Metrological Applications 10/31/2020 National Institute of Lasers and Optronics 35

Carousel Interferometer for Metrological Applications Simultaneous Measurement of Angle and Axis of Rotation while it Slips at the same time. 10/31/2020 National Institute of Lasers and Optronics, Islamabad 36

Simultaneous Measurement of Rotation of an Object and Rotation of its Axis 10/31/2020 37

Sagging of a Axially Symmetric Body 10/31/2020 Carousel Interferometer and it Metrological Applications 38

Carousel Interferometer for Metrological Applications • Future Challenging Directions – Detection by using Interferometry: • Continuous and Full Circle Rotation in either Direction (± 2 n) • Eccentricity and Precession in the Axis of Rotation probably simultaneously • Design of Totally Linear Technique for Angle, Axis and Slip in Axis of Rotation 10/31/2020 National Institute of Lasers and Optronics 39