LED count is the number buyers ask about and the number that tells you least. Two red light therapy beds with identical diode counts can differ severalfold in delivered dose, because output depends on drive current, bin quality, optics, afstand, and thermal management working together.
Golflengte, measured rather than printed
Most full-body red light therapy beds combine red emitters in the region of 630 naar 660 nanometers with near-infrared emitters around 810 naar 850 nanometer. Ask for spectrometer measurements of the actual production bin rather than trusting a component datasheet, and check the peak wavelength and full width at half maximum. A nominal 660 nanometer emitter supplied in a loose bin can drift several nanometers, and in a device where wavelength is the mechanism, that drift is a clinical and marketing problem, not a cosmetic one.
Irradiance only means something with a distance
Irradiance is quoted in milliwatts per square centimeter, and a figure without a measurement distance is not a specification. Light falls off rapidly with distance, so a value taken at the panel surface can be several times higher than the value at the user’s skin. Ask for the distance, the measurement grid, and the meter used, then compare like with like.
Convert to dose before comparing products. Fluence in joules per square centimeter equals irradiance in watts per square centimeter multiplied by exposure time in seconds. Een bestraling van 50 milliwatts per square centimeter maintained for ten minutes delivers 30 joules per square centimeter, because 0.05 multiplied by 600 equals 30. A bed advertising a very high peak figure with a two-minute preset may deliver less total energy than a modest panel running for fifteen minutes.
Uniformity across the treatment plane
A single center-point reading hides the problem most users actually experience: hot spots near the emitters and dead zones between them. Request a nine-point or twelve-point map across the usable treatment plane at the intended distance, and look at the ratio between the highest and lowest readings. Uniformity is also a comfort issue, since a hot spot becomes a complaint long before it becomes a safety report.
Thermal design and duty cycle
Output falls as junction temperature rises, so cooling is a performance specification disguised as a mechanical detail. Ask what happens during a sixty-minute continuous run at maximum output: how far irradiance drops, what the surface temperature of the panel and mattress reaches, and what the noise level is at one meter.
Then ask for the duty cycle and the derating policy. A bed rated for continuous commercial use in a clinic should not need a rest period between clients, and if it does, that belongs in the manual and in your booking schedule. Driver quality and heatsink design determine whether output at month eighteen resembles output on day one, and LED maintenance projections such as LM-80 data with TM-21 extrapolation are the evidence for that claim.
Controls, dosing, and software
A professional bed should let the operator set a dose rather than only a timer, and it should prevent accidental overexposure through preset limits and session lockouts. Session logging, user accounts, and exportable treatment records matter to clinic buyers and to your own post-market surveillance.
Ask how firmware is updated, whether the update is validated, and whether the device locks if an update fails. Where software contributes to the device’s safety or performance, IEC 62304 defines the lifecycle expectations your technical file will be measured against, and a red light therapy bed supplier with no software documentation is a supplier you will have to re-engineer later.
