20-Meter range laser distance meter for industrial use

• Grant number: 97/06877-7
• Support Opportunities: Research Grants - Innovative Research in Small Business - PIPE
• Start date: January 01, 1998
• End date: December 31, 2001
• Field of knowledge: Engineering - Electrical Engineering - Electrical, Magnetic and Electronic Measurements, Instrumentation
• Principal Investigator: Mario Antonio Stefani
• Grantee: Mario Antonio Stefani
• Company: Opto Médica Equipamentos Ltda
• City: São Carlos

Abstract

The purpose of this project is to develop laser distance meters with a range of from 0.5 to 20 meters. There are various ways of measuring distance with lasers. The most common is the geometric method also known as the laser triangulation method. Nonetheless, when a high degree of accuracy is required, this method is only useful for short distances, from 2 mm to 500 mm. The desired range is justified by the countless potential uses - civil engineering, measurement in grain silos, the level of liquids, detection and positioning of loads in freight cars, security systems, etc. For it to be feasible to use, however, the equipment must be low-cost and portable. Because of the limitations of the triangulation method for longer distances, new methods are needed to make the system feasible and practical. The most common is the telemetry method of short bursts of laser light, and this requires a careful electronic design project. The second method consists of comparing the phase of a modulated waveband of the laser beam with the returning signal. Opto Eletrônica S/A has already carried out the conceptual phase of developing this project. Based on this study a set of requirements was prepared, specifying the main features the product must have: measurement range of up 20m, accuracy of better than 1 cm, response time of no more than 1 second, visible laser of up to 5 MW of average power. The equipment must also be portable and be able to work in sunlight. (AU)