The Handheld Adjustable Light Source is Joinwit designed fiber optic tester, it aims at fiber network installation, fiber network engineering acceptance and fiber network maintenance. Combined usage with handheld optical power meter, it offers a quick and accurate testing solution on both SM and MM fibers. The tester provides 1 to 4 wavelengths and output power can be adjustable on customer requests. Also the tester features good appearance, good touch feeling and considerate humanity design.


  • Wave ID information can be transmitted when used with Optical Power Meter.
  • Tone generation, 270HZ,330HZ,1KHZ,2KHZ
  • Output power can be adjustable
  • Output power value is shown on LCD display
  • Intelligent backlight control (light intensity can be adjusted properly
    according to ambient light, which greatly reduced power consumption)
  • AA alkaline and AC adapter for power supply
  • Low battery indication


Model OLS
Operating wavelength(nm) 1310/1550;1310/1490/1550/1625(others specify on requests)
Applicable fiber SM,MM
Laser type FP-LD(others specify on requests)
Output Power(dBm) -5~-12dBm /(can be adjustable)
Adjustable step size(dBm) <0.5
Stability(dB,30min,20℃) 0.15
Modulation(Hz) CW, 270,330,1K,2K
Fiber Port FC/PC
Alkaline Battery 3*AA,1.5V
Power Supply Adaptor(V) 8.4
Battery Operating time(h) 45
Operation Temperature(℃) -10~+60
Storage Temperature(℃) -25~+70
Outline size(mm)/weight 180*90*45(250g)

Standard Package

All Models Optical Light Source, 3pcs 1.5V batteries, AC Adaptor, User Manual, Cotton swabs and Soft carrying case.

Optical Light Source / JW3109 Series

JW3109 Series

JW3109 optical light source can provide 1 to 4 output wavelengths to meet specific requirements, including the 650nm red source and the 1310/1550nm wavelengths for single mode fiber or the 850/1300nm wavelengths for multimode fiber, as well as other wavelengths according to customer needs. Together with the JW3208 optical power meter, it is a perfect solution for the fiber optic network characterization.


  • Provides 1~4 output wavelengths which can be optional according to customer’s needs
  • CW, 2Hz modulation output at 650nm, and CW, 270Hz,1KHz,2KHz modulation output at other wavelengths.
  • High stability of the output power
  • Stable output wavelength
  • Backlight LCD display supports night operation
  • Compact size and decent appearance
  • Large LCD, easy operation
  • Alternative 10 minutes Auto-off function conserving battery life

Application area

  • Maintenance in Telecom
  • Maintenance CATV
  • Fiber Optic Lab Testing
  • Other Fiber Optic Measurements


Type JW3109
Wavelengths(nm) 650 1310/1550 850/1300 850/1300/1310/1550
Emitter Type FP-LD,LED or others please specify
Typical Output Power (dBm) 0 -7dBm for LD, -20dBm for LED
Spectral Width(nm) 1. ≤10
Output Stability ±0.05dB/15mins; ±0.1dB/ 8hours
Modulation Frequencies CW,2Hz CW,270Hz,1KHz,2KHz
Optical Connector FC/ universal adaptor FC/PC
Power Supply Alkaline Battery(3 AA 1.5V batteries)
Battery Operating Time(hour) 45
Operating Temperature(℃) -10~+60
Storage Temperature(℃) -25~+70
Dimension(mm) 175x82x33
Weight (g) 295
Joinwit Recommendation
JW3109 Handheld Light Source is designed for optimal use with JW3208 Optical Power Meter for measuring optical loss on both single mode and multimode fiber cable.

Standard Package

All JW3109 Models JW3109 Optical Light Source, Protective Rubber Boot, 3pcs 1.5V batteries,User Manual, Cotton swabs and Soft carrying case.