Light output :990 lm
Color temperature :2700 / 4300 / 6000 K
LED power :11 W
Working distance :4.5–8.0″ (114–203 mm)
Spot diameter :2.0″ at 6.0″ dist.
(51 mm at 152 mm)
Spot illumination :6040 fc at 3.0″ dist.
(65,000 lx at 76 mm)
Inside diameter :4.05″ (102.9 mm)
Mounting diameter :4.70″ (119.4 mm)
Outside diameter :5.45″ (138.4 mm)


RL28Q User's Manual

Remote Control Demo

Model RL28Q" :: High intensity ring light with quadrant controller

  • High-intensity LED lamps arranged in quadrants
  • Touchpad controller allows external control via serial interface
  • Sealed body, IP65 rating
  • Compact size and versatile mounting
  • Optional dark field illuminator and polarizer
  • CE compliant

Controlled light output

Orled's RL28Q is perfectly suited for applications requiring sectional lighting control under high magnification. The RL28Q's quadrant controller has a convenient touchpad that transitions the brightness smoothly between no output and full output. The four quadrant zones can be individually turned on and off, allowing you to eliminate shadow for smooth, even illumination or create and control shadows to define surface details. The included QD01 controller keypad provides control over which quadrants are enabled, and the intensity of those active quadrants' output. The keys are lighted from behind for improved readability.

The light from 28 high-output LEDs is refracted through an innovative optical system to provide 65,000 lux at a working distance of three inches. Fresnel optics distribute light evenly around the diameter so that reflected points of light are not apparent when viewing shiny surfaces. The RL28Q is suitable for use in forensics, dental laboratories, gemology, and medical and industrial manufacturing. It is useful for viewing items such as circuit boards, electronics, jewelry, and highly reflective specimens in general.

Versatile mounting

The RL28Q accommodates mounting diameters between 3.8 and 4.7 inches for compatibility with a wide variety of microscopes and other optical systems. Soft point set screws hold the ring light securely to the microscope without causing damage. For custom mounting solutions, three #4-40 threaded holes are also provided on the top side of the ring light.

Sealed body

The outside lens of the RL28Q keeps the LEDs and electronics safe from splattering fluids, corrosive fumes, and damaging dust particles. The body is sealed to an IP65 rating. Custom sealing features may be added for use in particularly hazardous environments. The 62-mm threads at the end of the body may be used to mount a camera lens filter for protection of the microscope objective.

Intelligent thermal design

The LEDs used in the RL28Q are different from the traditional 5-mm bullet-shaped LEDs which are used in other ring lights. Ours provide a direct heat path from the light-outputting die to the circuit board; this allows the heat to be radiated off through the ring light. This is important because the temperature of the die determines the reliability and longevity of the LED. The claim made by some manufacturers that 5-mm LEDs will last 100,000 hours is not based on real-world applications. Please contact Orled for accurate longevity statistics for the LEDs that we use.

Optional accessories

Polarizer—The RL28Q can be supplied with a polarizer film and analyzer filter. This feature reduces glare from shiny surfaces and allows inspection of details and defects that would otherwise be concealed by reflected light.

Dark field adaptor—Remove the RL28Q from the microscope, install Orled's dark field adaptor, and place it under your subject facing up. The light refracted through the adaptor will light up the subject from underneath without entering the microscope objective. The viewer will see a subject with illuminated edges on a black background. This is an excellent way to inspect edge detail, and the best way to examine defects within transparent objects.


Model Description Price Order Qty.
1 2–9
Ring Lights
RL28Q-2700 Model RL28Q (2700 K) with quadrant driver $706 $642
RL28Q-4300 Model RL28Q (4300 K) with quadrant driver $706 $642
RL28Q-6000 Model RL28Q (6000 K) with quadrant driver $706 $642
POL-RL16 Polarizing filter $36 $36
DFA-RL16 Dark field adapter $33 $33