Dual-Laser Phase Rangefinder for Temperature-Compensated Accuracy
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing hand-held green laser rangefinders face challenges with high power consumption, high costs, and low measurement accuracy due to the use of single or dual green laser diodes, which are sensitive to environmental temperature changes.
Innovation Solution
A green laser phase rangefinder that combines a green laser diode with a red laser diode, using a direct digital synthesizer and frequency mixing to generate measurement signals, allowing the green laser to be turned off and the red laser to measure internal cavity distances, thereby reducing power consumption and costs while enhancing accuracy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single green laser diode is used to implement ranging, then the device structure is simple, but measurement accuracy is low due to temperature-induced phase shifts
Solution Approach 1:
The patent combines a green laser diode and a red laser diode into a single rangefinder device. The green laser diode performs external ranging while the red laser diode measures the internal cavity distance, creating a reference measurement that compensates for temperature-induced phase shifts and improves overall measurement accuracy.
Solution Approach 2:
The red laser diode acts as an intermediary reference system. By measuring the internal cavity distance with the red laser, the system obtains a reference value that reflects temperature-induced phase shifts, which is then used to compensate for errors in the green laser's external ranging measurements.
2Measurement precision
If two green laser diodes are used to implement ranging with internal cavity measurement, then measurement accuracy is improved, but power consumption and cost increase significantly
Solution Approach 1:
The patent changes the wavelength parameter of the laser diode used for internal cavity measurement from green to red. The red laser diode has lower power consumption and lower cost while still providing the necessary reference measurement for temperature compensation, thus maintaining measurement accuracy without the high power consumption and cost of using two green laser diodes.
3Measurement precision
If two green laser diodes are used to implement ranging with internal cavity measurement, then measurement accuracy is improved, but manufacturing cost increases significantly
Solution Approach 1:
The patent changes the wavelength parameter of the laser diode used for internal cavity measurement from green to red. The red laser diode has lower power consumption and lower cost while still providing the necessary reference measurement for temperature compensation, thus maintaining measurement accuracy without the high power consumption and cost of using two green laser diodes.
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
The solution achieves low power consumption, low costs, and high measurement accuracy by leveraging the red laser diode to compensate for environmental temperature effects, improving the overall performance of the rangefinder.
Implementation Method 1
A direct digital synthesizer (DDS) generates a signal with a frequency f1... The signal with f1 is amplified by an amplifier circuit and then modulated on a green laser diode 1... so that a laser beam 1 emitted by the green laser diode changes in brightness
Implementation Method 2
the laser beam 1 is reflected by a surface of the object, and reflected light is received by the APD through a receiving lens. The APD converts an optical signal into an electrical signal with a frequency being f1
Implementation Method 3
The signal with f1 and the signal with f2 are simultaneously input to a frequency mixing filter circuit, and an output signal of the frequency mixing filter circuit is input to the MCU to synchronize a measurement signal
Data Source
AI summary
Disclosed are a green laser phase rangefinder and a ranging method, which relate to the field of laser ranging. The rangefinder includes a direct digital synthesizer (DDS), a frequency mixing filter circuit, a microcontroller unit (MCU), a first amplifier circuit, an analog switch, a first laser beam module, a second laser beam module, a second amplifier circuit, an avalanche photodiode, a third amplifier circuit and band pass filter circuit, an analog-to-digital converter (ADC) module, a receiving lens, and a high-voltage circuit. A green laser diode is arranged in the first laser beam module; and a red laser diode is arranged in the second laser beam module. In the present disclosure, the green laser diode and the red laser diode are combined to implement ranging. The present disclosure features low power consumption, low costs, and high measurement accuracy.