Ellipsoidal Reflector Phase Detection for Laser Arrays
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing beam steering methods using movable reflectors are not agile and require mechanical motion, while electronic phase control methods face challenges with large steering angles and environmental protection for laser arrays.
Innovation Solution
A compact imaging system using a partially reflecting ellipsoidal or dual paraboloidal reflector to image and measure individual phases of a coherent laser array, allowing for electronic phase control and protection against environmental impacts.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If a movable reflector is used for beam steering, then the beam can be steered in a predetermined direction, but the system requires mechanical motion and is not agile
Solution Approach 1:
The patent replaces the mechanical movable reflector system with an electronic phase control system. By controlling the phase of individual laser beams in the array, the main interference lobe can be electronically steered to different directions without any mechanical moving parts, thereby achieving agile beam steering while eliminating mechanical complexity
Solution Approach 2:
The patent implements dynamic beam steering by electronically adjusting the phase relationships between laser array elements in real-time. This allows the beam direction to be changed rapidly and continuously without mechanical motion, transforming a static mechanical steering system into a dynamic electronic control system
2Device complexity
If electronic phase control is used for beam steering, then mechanical motion is eliminated, but the system faces challenges with large steering angles
Solution Approach 1:
The patent segments the beam steering function into individual phase control of each laser array element. By independently controlling the phase of each element, the system can synthesize beam patterns that achieve large steering angles through constructive and destructive interference, overcoming the limitations of conventional electronic phase control
Solution Approach 2:
The patent changes the phase parameters of individual laser array elements to achieve large steering angles. By dynamically adjusting phase relationships between elements, the system can steer the main interference lobe over large angular ranges while maintaining electronic control without mechanical parts
3Measurement precision
If a plane beam sampler is used for phase measurement, then beam phase locking can be implemented, but the sampled beam has fixed direction and limits steering agility
Solution Approach 1:
The patent replaces the plane beam sampler with an imaging system that forms images of laser array elements on a photodiode array. This optical imaging approach enables phase measurement without requiring the sampled beam to have a fixed direction, allowing simultaneous phase measurement and agile beam steering
Solution Approach 2:
The patent creates optical images (copies) of the laser array elements at a different location using imaging optics. These images are formed on a photodiode array for phase measurement, allowing the measurement system to observe the beam patterns without physically sampling the original beams, thereby enabling independent control of measurement and steering functions
4Measurement precision
If the laser array is exposed for imaging and phase measurement, then phase detection can be performed, but the array is vulnerable to environmental impacts
Solution Approach 1:
The patent implements a partially reflecting cover that serves multiple functions simultaneously: it protects the laser array from environmental impacts while still allowing optical imaging and phase measurement to occur through the cover. This multi-functional element eliminates the need to choose between protection and measurement capability
Solution Approach 2:
The partially reflecting cover acts as an intermediary between the laser array and the external environment. It provides physical protection while maintaining optical transparency for imaging purposes, mediating between the need for protection and the need for phase measurement access
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enables agile beam steering over large angles without mechanical motion and provides protection for the laser array, improving the efficiency and stability of beam steering systems.
Implementation Method 1
a partially reflecting ellipsoidal or dual paraboloidal reflector with two focal areas to image the laser array at one of the focal areas to the other focal area
Implementation Method 2
Illumination of this image with a phase modulated beam from a reference laser coherent with the laser array allows the application of dithering techniques to measure individual phases of beams from array
Implementation Method 3
a partially reflecting ellipsoidal or dual paraboloidal reflector
Data Source
AI summary
A method and apparatus for measurement of individual phases of beams from a beam steering laser array relative to a reference laser beam. The disclosed method and apparatus is based on the use of a partially reflecting ellipsoidal reflector or dual paraboloidal reflector having two focal areas to make an image of the laser array located in one of the focal areas appear at the other focal area. Illumination of this image with a phase modulated beam from a reference laser coherent with the laser array allows the application of dithering techniques to measure individual phases of beams from array. Any laser beam in the array or a separate laser coherent with the laser array can be used as a reference beam. In addition, the partially reflecting ellipsoidal reflector or dual paraboloidal reflector can provide protection for the beam steering laser array from environmental impacts or damage.