Many sensors and applications that Visidyne Inc. has developed are based on the unique optical phase measurement techniques that Visidyne has perfected that allows for a precision of one part per billion in the comparative phase between two or more electromagnetic signals.

Optical Phase Measurements

Monocular 3-D Imaging

monocular imager that is capable of generating 3-D imaging at the sub-millimeter level has been invented and is under development by Visidyne as a prototype for a NASA optical hazard landing system. The underlying patented technologies provide for a system of medium and high-powered, infrared systems that illuminate a scene with intensity modulated light at frequencies up to 10 MHz. This yields an image of the scene and provides a time/distance scale that a specialized CCD chip converts the received backscatter light into a base band signal to generate range and intensity values for each pixel. In addition a 1.2Kw illuminator was designed and built for hi-power, long-range illumination.

Applications: Landing system, industrial inspection, medical applications, facial recognition, identification of military targets for kinetic hit-to-kill interceptors and targets under difficult conditions of low contrast, partially obscured, and/or behind foliage.

B-Field Communication and Navigation

he global positioning system, GPS, is one of the important technical accomplishments of the United States. It has a pervasive influence on many elements of DoD and civilian related activities. However, it has operational limitations, which preclude its use in many situations as in cases of signal blockage, e.g., under tree canopies, in dense urban environments, underground tunnels, caves, and under water. Visidyne has developed a concept to address these limitations with an innovative design that closely parallels GPS, but uses AC, non-propagating magnetic fields for precise, accurate location and navigation where GPS does not work. Operationally, it would use multiple, four or more, local, i.e., B-field pseudolites, pre-positioned around an area that would propagate time stamped signals into a volume under interrogation. This development can be used for local communication in high-rise buildings when for example, due to fires or power outages the conventional communication systems are disabled. Some key components of the design are under patent application.

Applications: Indoor, underground, underwater navigation and communications.

Ultrasensitive Magnetometer

Visidyne has recently developed and demonstrated an

improved magnetic sensor under DARPA sponsorship. The Optical Faraday Magnetometer (OFM) has sensitivities at the pico Tesla/Hz^1/2 level that approaches the performance of the cryogenic SQUID sensors but operates at room temperature. The OFM solid-state sensor is small (the size of a pencil), low-weight, requires little power and operates in the critical frequency domain from less than 0.1 Hz to over 1 kHz. Patent is applied for improvements on the OFM.

Applications: Underwater surveillance, IED detection, Security screening. Situational Awareness Surveillance of target satellites.

MicroRanger™ and MicroVibrometer

icroRanger™ is a patented precision non-contact distance and vibration measurement instrument. It uses intensity modulated laser light to measure displacements with micrometer precision at kilohertz bandwidths up to tens of meters from the probe depending upon the level of laser illumination.

Based on this technology, a laser-motion-tracking-system that measures displacements with micron precision was developed to enable linear motion analysis of a wide variety of objects. As a stand-alone instrument it can either be incorporated into an application or carried between measurement locations. As a motion study tool it can be connected to a PC for high-speed data collection.

Applications: Wide industrial and scientific use where precision displacement measurements are required, for example for extended structures in space, for satellite constellation station keeping, or for remotely monitoring the vibrational characteristics of large structures such as bridges.

MicroTracker™ - 3-D Optical Tracking

isidyne has developed and implemented a high speed, high-resolution active optical motion tracking capability. This patented technology delivers accurate, real-time 6 degrees of freedom tracking at speeds up to 500Hz. This technology uses small eye-safe lasers and receivers assembled from commercially available components. It can be used to remotely monitor the position and motion of industrial tools such as those found on automotive production-line welding machines. Visidyne has successfully implemented this technology into a cockpit head-tracking solution for a DoD customer that is independent of magnetic interference or gyroscope controlled systems that require periodic re-alignment.

Applications: Virtual reality simulations, human movement tracking for computer control, and industrial tracking of tools.

Angular Encoder

he Visidyne Angular Encoder is a non-contact shaft-encoding scheme using passive optics, an LED, and a detector. The encoder uses an LED to illuminate a rotating shaft and uses the reflected light, from the shaft-end, to measure angular position (rotation angle). The reflected light impinges on a proprietary Tri-Phase detector that outputs a signal proportional to the angular position, absolute over 360 degrees. The innovation of this technology is in the Tri-Phase measurement. The Tri-Phase measurement allows for wide variation between encoder and shaft distance and variations in temperature. The Visidyne Encoder is a non-contact measurement device that obviates the need to attach the encoder to the shaft. It is high-resolution, low power with the following advantages: not susceptible to EMI, RFI, or vibration, non-contact measurement (no loading effects, no bearings), wide tolerances between encoder and shaft-end (5mm – 50mm), no maximum mechanical speed.

Applications: Precision position control of automotive, industrial, defense, space, medical, and toy rotational systems.

Hyper Dense Wavelength Multiplexing (HDWM)

DWM expands the use of available fiberoptic cable by multiplexing any of the existing multi-color channels by a factor of as much as two orders of magnitude. Since the HDWM system is highly linear there is no crosstalk between these channels and this allows for a much more efficient use of the cables already installed in metropolitan areas.

Applications: This technology is appropriate for metropolitan-area fiber-optic networks, where there are already many multi-color channels. When there will be a need to increase the number of discrete channels, the high-fidelity nature of this approach to increase each optical channel's usage will permit as much as a hundred-fold increase in the aggregate data rate in each of the existing channels.

Photonic A to D Converter

his technology is a continuation of Visidyne’s efforts in the application of optical phase encoding and detection to the problem of digitizing and transporting wideband analog signals. Contemporary schemes generally encode data by modulating the intensity of an optical beam in a fiber. Visidyne has demonstrated that by modulating the phase of the optical carrier, rather than its intensity, both greater channel capacity, more gigabits-per-second, and greater linearity can be achieved. By adding a photonic process in front of conventional electronic analog-to-digital converters, the resolution of present day and future electronic ADCs can be improved by a factor from 2 to 3 bits at any sample rate, with similar reductions in inter-modulation distortions. Since this Photonic Front-End can be remote from the electronic digitizer, connected to the data destination by a pair of optical fibers, it can be used as a high-bandwidth data link as well. The hardware at the data source is electrically passive and potentially very compact and rugged making it ideal for applications such as transport of RF signals from remote antennas with high fidelity and low distortion.

Applications: Fiber optics and RF communications.

Photonic Clock

The most common options for precision clocks are quartz crystal oscillators in the form of Oven Controlled Crystal Oscillators (OCXOs) that use a high quality mechanical resonator, the quartz crystal element, to stabilize the frequency of an oscillator and atomic clocks that use a hyperfine transition in an excited gas, e.g., Cs or Rb to stabilize a frequency. OCXOs can have excellent short-term stability. Long-term stability is limited due to aging effects such as out-gassing and de-crystallization changing the crystal resonance frequency. Atomic clocks have relatively poor short-term stability due to the complex electronic chain required, but have the best long-term stability.

Visidyne has developed a Photonic clock that can achieve the best capabilities of both, the excellent short-term stability of a high performance crystal clock along with a long-term stability approaching that of an atomic clock. While the underlying principles of the Photonic clocks are not new, the technologies to implement them are recent and their use novel, including such Photonic elements as low power, energy efficient, vertical cavity surface emitting laser (VCEL) diodes, low loss single mode optical fiber having minimal mass even in substantial lengths, and fast optical detectors.

Visidyne has demonstrated a Photonic clock consisting of diode laser, optical delay line and detector/receiver that are used to design RF oscillators at 2 to 10 Ghz, with less phase noise in a smaller footprint and at lower power consumption than existing, all electronic designs.

Applications: digital electronics, GPS, better cell phone technology with better RF throughput.

Cloud Characterization for Remote Sensing

SAMNET Sensor

AMNET is a unique, patent-pending instrument complex that measures the radiance of the solar disk and the associated aureole resulting from the passage of solar radiation through atmospheric aerosols and clouds. The radiance of the solar disk measures the cloud optical depth. This is one of the two most important optical measures of cloud radiative effects. The aureole measurements made simultaneously by the SAMNET sensor yields information on the Forward Scattering of the sunlight that is defined by the ice/water composition of the cloud along the line of sight and, as such, SAMNET is important for understanding cloud transmissive effects as well as particle size and ice content of cirriform clouds. SAMNET is accompanied by a sophisticated modeling software package that provides characterization of atmospheric conditions.

Applications: Remote sensing, cloud characterization, weather and climate studies.

CloudScape^® Tools for 3-D, Physics-based Cloud Visualization

loudScape^® is a family of copyrighted software tools that facilitates the radiometrically accurate modeling and visualization of weather clouds, nuclear detonation clouds as well as munitions- and bomb-generated dust clouds. The CloudScape tools include: (1) a collection of tools for generating 3-dimensional databases for modeling and visualizing weather clouds. The toolkit includes a non-real-time visualization capability, (2) a collection of tools for generating 3-dimensional databases for modeling and visualizing nuclear detonation and munitions clouds.

Applications: Atmospheric research, battlefield effects, chemical and biological releases. Modeling effects of chemical, biological, and high explosive and nuclear detonations, situational awareness, home security.

Meteorological Balloon Launcher

eteorological data from radiosondes provide an essential part of the knowledge of both global and local atmospheric conditions. Although worldwide launching of radiosondes has been done for many years, it remains a labor intensive and, therefore, an expensive operation. The pre-launch preparation and launch of a typical radiosonde requires the efforts of a skilled technician for over an hour for each launch. Because the daily launches can be scheduled over 24 hours, seven days a week, multiple technicians are required to support a continuous launching cycle. Visidyne, Inc. initiated the development of an Automatic Radiosonde Launcher to automate this complicated process and demonstrated a prototype launcher that has led to the issuance of two patents.

Applications: Many thousands of weather balloons are launched by hand every year. The development of an automatic launch system provides a cost effective, reliable alternative. Its application would be global and particularly valuable for remote locations.

Electro-Optical Instrumentation

PEELS - Portable Eye safe Environment Lidar System

isidyne, Inc. has developed and field-tested an eye safe, skin safe, easily-transportable, targeting and tracking lidar system, called PEELS. An innovative feature of this lidar is the capability to alternate the polarization of each pulse of the transmitted laser beam. Polarization analysis of the backscatter is performed in the receiver and provides information of the ice or water constitution of the clouds along the line of sight. PEELS is a turnkey system, two of which are presently in the field being operated by the DoD, one in an around-the-clock study over the last two years. The PEELS power level is many orders of magnitude greater than conventional ceilometers and, hence, can penetrate and delineate thicker clouds and measure higher altitude cloud effects.

Applications: Meteorological research monitoring of dust, volcanic and ice clouds, crop dusting monitoring, obstacle avoidance for trains, ships, and aircraft. Used to detect the exhaust particulates from tanks and trucks hidden by the terrain and from the dust raised by helicopters hidden by trees or by the terrain. Used to measure clouds to distinguish water droplet clouds from ice clouds by the difference in the de-polarization effects. It has been flown on the US Air Force FISTA laboratory aircraft to measure the clouds below the airplane during polarization measurements from cloud-scattered sunlight.

Instrumentation & Systems Developed by Visidyne

Space Instrumentation X-Ray Instrumentation

Space Particle Imager for Space Debris Measurements Rocketborne Bremsstrahlung X-Ray Detector

MSX Xenon Lamp Particulate Monitor X-Ray Microscope Optics

MSX Krypton Lamp Radiometer Water Vapor Monitor X-Ray Telescope Optics

Lidar Systems Particle Instrumentation

Portable Eye Safe Targeting/Tracking Lidar Rocketborne Retarding Potential Analyzers for Measurements of Vehicle Potentials

Balloonborne Multiwavelength Incoherent Lidar - (ABLE) Rocketborne Electrostatic Analyzers for Measurements of Artificial and Natural Aurora

Balloonborne Coherent CO₂ Lidar Rocketborne Electron Accelerators for Upper Atmospheric Excitation

Sounding Rocket Lidar System Alpha Detectors

Infrared Instrumentation Vapor Releases

Balloonborne LWIR Radiometer System Water Vapor Release Module

SWIR Imager and Interferometer for Groundbased STS Plume Measurements Uranium Vapor Release Module

Airborne Target Discrimination Imager for Optical Clutter Suppression

Groundbased Background Optical Suppression Dual Beam SWIR Interferometer System Balloon Payloads

Airborne SWIR Scanning Imager Balloonborne Payload System for Precise Pointing of IR Sensors - BAMM

Balloonborne Lidar for Atmospheric Rayleigh, Mie and Raman Measurements - ABLE I, II, III

Visible Instrumentation Balloonborne Payloads with Precision Pointing and Tracking for UV-Visible Sensors – KESTREL

Rocketborne Visible Spectrometers for Measurements of Artificial Aurora Balloonborne CO₂ Coherent Lidar

Rocketborne Photometers for Measurements of Artificial and Natural Aurora

Rocketborne Scanning Photometer for Measurements of Artificial Aurora

VUV/UV Instrumentation

Rocketborne UV Spectrometers for Measurements of Artificial and Natural Aurora

Rocketborne UV Photometers for Measurements of Artificial and Natural Aurora

Rocketborne and Laboratory VUV Photoelectron Spectrometers

Rocketborne VUV Image Scanner

Rocketborne VUV Ionization Detector

Rocketborne VUV Photometers

Code	Customer	Description
NucSim	DTRA	Computes RF and IR operability in a nuclear disturbed environment
VECTR	USN	Spatial and Spectral Tracking of ENVAR Signals
ENVAR	USN	Signal Association Using Envelope Coherence
HiSEMM	USASSDC	Simulation-Level Nuclear Environments for Infrared and Radar Sensors
ATHENA	DNA	Heated Gas Emissivities and Opacities
SSGM	NRL/DNA	Strategic Scene Generation Model
IRSim	DNA	Simulator for Nuclear Scene Generation
PEM	DNA	Phenomenology Engagement Module – A Fast NORSE Derivative
NORSE	DNA	Nuclear Optical and Radar Systems Effects Code
ROSCOE	DNA/USAF	Radar and Optical Systems Code
NADIR	DNA/USAF	Nuclear-Induced IR Emissions Code for Air Force Systems
DND	NASA/USAF	Prediction of Polyatomic, Elevated Temperature and Pressure, Line Positions and Strengths
VOSEC	ATSA	System Evaluation of Effects of IR Backgrounds and Clutter
VERAA	ATSA	Updated Version of TACTIR
TACTIR	USAF	Nuclear Burst Emission Seen Through the Atmosphere for Tactical Applications
SLAM	DNA	Visible and Nuclear Induced Emission Code
HIRAM	USAF	Non-equilibrium Atmospheric Limb IR Emission Code
SIM	USAF/IBM	Satellite System Simulation Code
SIMDRV	USAF	Nuclear Simulation Code for Use in Satellite System Predictions
FASCODE I	USAF	First Version of High Resolution, Line-by-Line Atmospheric Transmission and Emission Code
LOWTRAN I	DNA/USAF	First Version of the Standard Lower Resolution Atmospheric Transmission Code (Part of OPTIR)
OPTIR	DNA/USAF	First Optical/Infrared Nuclear Prediction Code

Space Instrumentation	X-Ray Instrumentation
Space Particle Imager for Space Debris Measurements	Rocketborne Bremsstrahlung X-Ray Detector
MSX Xenon Lamp Particulate Monitor	X-Ray Microscope Optics
MSX Krypton Lamp Radiometer Water Vapor Monitor	X-Ray Telescope Optics

Lidar Systems	Particle Instrumentation
Portable Eye Safe Targeting/Tracking Lidar	Rocketborne Retarding Potential Analyzers for Measurements of Vehicle Potentials
Balloonborne Multiwavelength Incoherent Lidar - (ABLE)	Rocketborne Electrostatic Analyzers for Measurements of Artificial and Natural Aurora
Balloonborne Coherent CO₂ Lidar	Rocketborne Electron Accelerators for Upper Atmospheric Excitation
Sounding Rocket Lidar System	Alpha Detectors

Infrared Instrumentation	Vapor Releases
Balloonborne LWIR Radiometer System	Water Vapor Release Module
SWIR Imager and Interferometer for Groundbased STS Plume Measurements	Uranium Vapor Release Module
Airborne Target Discrimination Imager for Optical Clutter Suppression
Groundbased Background Optical Suppression Dual Beam SWIR Interferometer System	Balloon Payloads
Airborne SWIR Scanning Imager	Balloonborne Payload System for Precise Pointing of IR Sensors - BAMM
	Balloonborne Lidar for Atmospheric Rayleigh, Mie and Raman Measurements - ABLE I, II, III
Visible Instrumentation	Balloonborne Payloads with Precision Pointing and Tracking for UV-Visible Sensors – KESTREL
Rocketborne Visible Spectrometers for Measurements of Artificial Aurora	Balloonborne CO₂ Coherent Lidar
Rocketborne Photometers for Measurements of Artificial and Natural Aurora
Rocketborne Scanning Photometer for Measurements of Artificial Aurora

VUV/UV Instrumentation
Rocketborne UV Spectrometers for Measurements of Artificial and Natural Aurora
Rocketborne UV Photometers for Measurements of Artificial and Natural Aurora
Rocketborne and Laboratory VUV Photoelectron Spectrometers
Rocketborne VUV Image Scanner
Rocketborne VUV Ionization Detector
Rocketborne VUV Photometers

Optical metrology