Sensitive, Long Range
Cloud measurement with advanced signal processing
Related Documents WEATHER Related Documents WATER Related Documents ENERGY Related Documents MACHINES Related Documents STRUCTURES Related Documents EARTH


The CS135 LIDAR Ceilometer measures cloud height and vertical visibility for meteorological and aviation applications. Using LIDAR (light detection and ranging) technology, the instrument transmits fast, low-power laser pulses into the atmosphere and detects back-scattered returns from clouds and aerosols above the instrument.

Read More

Benefits and Features

  • Novel split-lens design for high signal-to-noise ratio, maximized detector sensitivity, and extended range
  • Robust, reliable Campbell Scientific electronics
  • Advanced signal processing
  • High performance sensor at a competitive price
  • Integrated heater, blower, and radiation shield
  • Filter to protect detector from direct sunlight


Technical Description

The CS135 employs a novel split-lens design to increase optical signal-to-noise ratio over other instruments while maintaining Class 1M eye safety by integrating larger optics into a compact package. This optical design provides an alternative to traditional biaxial or common-optics designs. The optical isolation of traditional biaxial systems is maintained to increase detector sensitivity, while the low overlap height of common-optics systems is incorporated to allow measurements at close ranges.

This hybrid approach, along with state-of-the-art electronics measures cloud height and vertical visibility with high accuracy, stability, and repeatability. With a rugged environmental enclosure that protects the instrument from the harshest conditions, the CS135 measures the atmosphere with high stability and repeatability. The enclosure provides sufficient space to house a Campbell Scientific CR1000 datalogger and communications peripherals.



  • 100.0 x 33.0 x 31.6 cm 
  • (39.4 x 13.0 x 12.4 cm)
  • Weight without cables: 32 kg (71 lb)
  • Weight without cables, outer cowling, and enclosure: 25 kg (55 lb)
  • Temperature Range: -40° to 60°C (-40° to 140°F)
  • Humidity Range: 0 to 100% RH

Instrument Performance

  • Maximum Reporting Range: 
    10 km (32,800 ft)
  • Minimum Reporting Resolution: 
    5 m (15 ft)
  • Hard Target Range Accuracy: 
    ±0.25%, ±4.6 m
  • Reporting Cycle: 2 to 120 s
  • Cloud Layers Reported: Up to four layers
  • Vertical Visibility: Reported when no clouds selected
  • Laser Wavelength: 905 nm
  • Eye Safety: Class 1M


  • Power: 110, 115, 230 Vac ±10%, 
    50 to 60 Hz, 470 W maximum
  • Battery: Internal 12 Vdc, 2 Ah battery provides 1 hr measurement without blower/heater, in the event of mains failure.
  • Laser safety compliance: EN60825-1:2001
  • Electrical safety compliance: EN61010-1
  • Interfaces
    Data: RS-232,  RS-485
    Maintenance: USB 2.0 (USB 1.1 compatible)
    Baud Rate: 300 to 115200 bps


Datalogger Considerations

Compatible Dataloggers

CR200(X) Series CR800/CR850 CR1000 CR3000 CR5000 CR7X CR9000X

Related Documents