In the evolving field of laser rangefinding, ERDI TECH LTD has introduced a groundbreaking method and device for target acquisition in laser rangefinders, designed to maintain high measurement accuracy while minimizing false alarms—without increasing laser emission power.
Background: Challenges in Traditional Rangefinding
Traditional laser rangefinders operate by emitting narrow laser pulses (typically 10–20 ns) toward a target and measuring the round-trip time of the reflected pulse to calculate distance using the formula:
L = (C × Td) / 2
Where:
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L is the measured distance
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C is the speed of light
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Td is the time delay between the transmitted and received signal
However, factors like sunlight interference, ambient noise, and low signal return from targets can reduce accuracy. Many existing solutions attempt to overcome this by increasing laser power—at the cost of efficiency and safety.
ERDI’s Solution: High-Precision Measurement Without Power Increase
ERDI TECH LTD has developed an innovative digital signal integration and servo control method that filters ambient noise, allowing for accurate target signal detection even in noisy environments. This new approach maintains a fixed false alarm rate through adaptive threshold adjustment and advanced signal processing.
Key Features of the Target Acquisition System
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Laser Emission Module:
Emits precise, high-frequency laser pulses (10–20 ns) according to a pre-defined timing sequence. -
False Alarm Rate Control:
A feedback-controlled comparator adjusts its threshold voltage in real time, ensuring a fixed false alarm rate regardless of environmental noise. -
Digital Signal Processing & Integration:
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Converts serial output from the receiver into parallel data
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Stores each emission's signal data in memory
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Integrates data across multiple cycles to enhance signal strength and suppress noise
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Target Detection Logic:
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After a defined number of laser pulses, the system identifies the address with the highest accumulated signal value—pinpointing the target distance
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Increases laser emission cycles if needed, boosting the signal-to-noise ratio without increasing power
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Microprocessor-Controlled Calculation:
The system uses a microprocessor for real-time decision-making, mapping signals to memory, calculating ratios of true detections, and determining valid target distances. -
Distance Measurement Unit:
Incorporates high-speed data latches, multiplexers, and a decoder to accurately determine range while filtering out invalid readings.
Performance Highlights
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False Alarm Immunity:
Maintains a fixed false alarm rate using servo control and adaptive thresholding -
Extended Measurement Range:
Achieves greater detection distance without increasing laser output power -
High Sensitivity:
Efficiently detects weak signals in the presence of high background noise -
Reduced Timing Jitter:
Ensures stable distance output by compensating for signal amplitude variations -
Safety and Efficiency:
Designed for low-power operation with Class 1 eye safety compliance
Applications
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Military-grade laser targeting and ranging systems
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Industrial automation and safety zones
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UAV-based remote sensing
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Perimeter security and surveillance systems
Conclusion
ERDI TECH LTD’s innovative laser rangefinding solution addresses one of the core limitations of traditional systems—noise vulnerability—by implementing digital integration, fixed false alarm rate control, and precision target acquisition algorithms. This not only boosts measurement accuracy and range but does so in a low-power, cost-efficient, and environmentally friendly manner.
For detailed specifications and diagrams, or to explore our full line of precision laser rangefinding technologies, visit:
👉 www.erditechs.com
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