UNI-T LM Series Laser Rangefinder Operating Manual

Introduction

The LM Laser Rangefinder is a portable photoelectric device that combines a telescope with a laser to measure angle and distance. Key aspects include:

• The ability to measure the distance of fixed or slow-moving objects within the observable range. The LM series offers high accuracy, short measurement times, an intuitive display, and power saving via auto shut-off.
• The rangefinder utilizes the latest technology to measure target distance and angle. It can display target distance, relative height, horizontal distance, and the angle between the device-to-target line and the ground plane (elevation or depression angle).

The device emits low and safe laser power, making it safe for eyes. LM series rangefinders are small, lightweight, and portable. They are powered by rechargeable lithium batteries, offering long working hours.

Laser Rangefinders are applicable in various fields, including engineering surveying and measurement, power line inspection, forestry prospect & design, construction building, internet planning survey & design, communication repairing, navigation measuring, and animal surveying and hunting.

Features

• Multifunctional LCD sighting telescope
• Silent operation and auto shut off
• Uses pulse laser.
• Fast distance measurement (Note: Maximum distance will change with the reflectivity of different objects and the environment).

Appearance

The device features several key components:

• 1. Laser Transmitting Objective Lens
• 2. Laser Receiving Objective Lens
• 3. Mode Switching Key
• 4. Power/Transmitting Key
• 5. Observing Eye Lens/LCD
• 6. Rotary Focusing
• 7. Micro USB Charging Port and indication light

Eye Lens LCD Symbols

The device's LCD displays various indicators:

• 1. Distance measurement indicator
• 2. Measuring mode
• 3. Angle Data
• 4. Horizontal and height data
• 5. Target indicator
• 6. Horizontal and height measurement indicator
• 7. Distance Unit
• 8. Flag indicator

Operation Introductions

Device Controls

• The device has two keys: the power/transmitting key and the MODE key.
• Press the power key for approximately 1 second to turn on the device.
• Short press the MODE button to switch between two measurement modes:
  • Multifunctional measurement modes (distance, height, angle, continuous measurement, and flag locking function).
  • Speed measurement mode (indicated by 'SPD').

Performing Measurements

• Press the [power/transmit key] once for a single distance measurement. A circle appears in the center of the LCD during measurement.
• After measurement, the direct distance to the target is displayed at the top of the screen. Vertical height or pitch angle data is displayed at the bottom. If the target is unclear or out of range, '--' will be displayed.
• To measure continuously, keep pressing the [power/transmit key]. The flag lock function is available in Golf mode. In common scanning mode, distance data updates constantly. Release the [power/transmit key] to stop scanning.

Speed Measurement

• Conditions: The object must be perpendicular to the objective lens, and the target must be moving at a constant speed.
• Operations: Short press the MODE button to select speed mode ('SPD' will be displayed). Short press the [power/transmit key]; the bull's-eye reticle will track the measured object until a result is obtained.

Device Behavior and Battery

• The device automatically shuts off after 10 seconds of inactivity.
• A [low-battery-indicator] symbol indicates low battery, and the battery should be charged.
• Battery lifetime is approximately 8000 measurements under normal temperature. A measurement cycle includes target focus, measurement, and auto power-off. Actual data may vary based on temperature, target shape, and color.
• LM series devices use a 3.7V rechargeable lithium battery. Disconnect the charging cord after full charge to prolong battery life.

Diopter Adjustment

• Adjust the diopter to achieve clear focus on the lens. Turn the eye lens counter-clockwise until the screen is in focus.

Precautions

Laser Safety and Measurement Principle

• The LM Laser Rangefinder transmits infrared pulse laser which is invisible and harmless to eyes. The infrared pulse laser reflects back to the optics receiver from the target. By measuring the round-trip time of the pulse laser from the finder to the target, the system calculates the distance.
• Maximum range depends on the target's reflectivity, color, surface, finish, dimension, and real shape.

Optimal Measurement Conditions

• Sunny day
• Target is bright
• Target surface is glossy
• No impurity in air
• Target surface is of high-reflection

Factors Affecting Measurement Range and Accuracy

• Target is black
• Snowy, rainy, or foggy conditions
• Target surface is of diffused reflection
• Target is tiny or micro
• Measurement through glass
• Target is dynamic

Battery Information

• Li-ion battery: Operating Temperature (-10°C to 60°C); Rated capacity: 1500mAh; Dimensions: 52.5*42.5*6.5mm; Warranty: One Year.

Handling and Maintenance

• Do not touch the lens surface with fingers to avoid damaging the lens coating.
• The device is precisely calibrated; do not dismantle it.
• Clean exposed lenses lightly with a glass cloth. Avoid using other materials that could damage the optics glass coating.
• Avoid crashing or pressing the device during use or transport. Do not expose it to heat or corrosion.
• Store the device in dry, cool, and ventilated environments. Avoid direct sunlight, sudden temperature changes, and dust.
• If the device is damaged, send it to an authorized service center for repair instead of attempting self-repair.
• Do not point the device directly at the sun or strong light sources.

Specifications

Notes on Accuracy

• Accuracy is tested under optimal conditions. Actual measurements may vary based on target and environment.
• Measurement return time is between 1 to 4 seconds.
• Angle error is tested under optimal conditions.