Optical time of flight and an autofocus system using a variable focal length lens

2021 ◽  
Author(s):  
Juan Manuel Franco Sanchez ◽  
Joel Cervantes Lozano ◽  
Keiichiro Kagawa ◽  
Hajime Nagahara ◽  
Yoshio Hayasaki
Keyword(s):  
Focal Length ◽  
Time Of Flight ◽  
Focal Length Lens ◽  
Optical Time

scholarly journals Ultrasound Imaging by Thermally Tunable Phononic Crystal Lens

2021 ◽  
Vol 22 (15) ◽  
pp. 7966
Author(s):  
Yuqi Jin ◽  
Arup Neogi
Keyword(s):  
Solid State ◽  
Signal To Noise Ratio ◽  
Focal Length ◽  
Phononic Crystal ◽  
Time Of Flight ◽  
Low Frequency ◽  
Axial Direction ◽  
Long Distance ◽  
Focal Length Lens ◽  
Flight Mode

This work demonstrates the detections and mappings of a solid object using a thermally tunable solid-state phononic crystal lens at low frequency for potential use in future long-distance detection. The phononic crystal lens is infiltrated with a polyvinyl alcohol-based poly n-isopropyl acrylamide (PVA-PNIPAm) bulk hydrogel polymer. The hydrogel undergoes a volumetric phase transition due to a temperature change leading to a temperature-dependent sound velocity and density. The temperature variation from 20 °C to 39 °C changes the focal length of the tunable solid-state lens by 1 cm in the axial direction. This thermo-reversible tunable focal length lens was used in a monostatic setup for one- and two-dimensional mapping scans in both frequency domain echo-intensity and temporal domain time-of-flight modes. The experimental results illustrated 1.03 ± 0.15λ and 2.35 ± 0.28λ on the lateral and axial minimum detectable object size. The experiments using the tunable lens demonstrate the capability to detect objects by changing the temperature in water without translating an object, source, or detector. The time-of-flight mode modality using the tunable solid-state phononic lens increases the signal-to-noise ratio compared to a conventional phononic crystal lens.

Optical time-of-flight and absorbance imaging of biologic media

Science ◽  
1993 ◽  
Vol 259 (5100) ◽  
pp. 1463-1466 ◽  
Author(s):  
D. Benaron ◽  
D. Stevenson
Keyword(s):  
Time Of Flight ◽  
Optical Time

Femtosecond optical time-of-flight measurement of the electron velocity in GaN

2000 ◽  
Author(s):  
M. Wraback ◽  
H. Shen ◽  
J. C. Carrano ◽  
T. Li ◽  
J. C. Campbell
Keyword(s):  
Time Of Flight ◽  
Electron Velocity ◽  
Flight Measurement ◽  
Optical Time

Optical time‐of‐flight measurement of carrier diffusion and trapping in an InGaAs/InP heterostructure

1987 ◽  
Vol 51 (8) ◽  
pp. 590-592 ◽  
Author(s):  
D. J. Westland ◽  
D. Mihailovic ◽  
J. F. Ryan ◽  
M. D. Scott
Keyword(s):  
Time Of Flight ◽  
Carrier Diffusion ◽  
Flight Measurement ◽  
Optical Time

scholarly journals IR femtosecond pulsed laser-based fiber Bragg grating inscription in a photonic crystal fiber using a phase mask and a short focal length lens

2018 ◽  
Vol 26 (11) ◽  
pp. 14741 ◽  
Author(s):  
Tigran Baghdasaryan ◽  
Thomas Geernart ◽  
Adriana Morana ◽  
Emmanuel Marin ◽  
Sylvain Girard ◽  
...  
Keyword(s):  
Photonic Crystal ◽  
Fiber Bragg Grating ◽  
Photonic Crystal Fiber ◽  
Focal Length ◽  
Pulsed Laser ◽  
Phase Mask ◽  
Bragg Grating ◽  
Crystal Fiber ◽  
Focal Length Lens ◽  
Short Focal Length

Electrical and optical time‐of‐flight experiments in GaAs/AlAs superlattices

1989 ◽  
Vol 54 (26) ◽  
pp. 2656-2658 ◽  
Author(s):  
H. Schneider ◽  
W. W. Rühle ◽  
K. v. Klitzing ◽  
K. Ploog
Keyword(s):  
Time Of Flight ◽  
Optical Time

Optical time‐of‐flight investigation of the exciton transport in silicon

1987 ◽  
Vol 61 (4) ◽  
pp. 1480-1485 ◽  
Author(s):  
B. Laurich ◽  
H. Hillmer ◽  
A. Forchel
Keyword(s):  
Time Of Flight ◽  
Exciton Transport ◽  
Optical Time
Sign in / Sign up

Export Citation Format

Share Document