BlissGlows LaserRevive 82 (Hubei YJT HAT-01)

Every figure below is published by the manufacturer or taken from its FDA filing, with the source next to it. We have not measured any of them ourselves.

Published specifications

Emitters
82 × laser diodeSource: K232356 p.7
Wavelength
650 nmThe filing states 650nm for the subject device. The ±5nm tolerance appears in the column for predicate K203826, not the subject's.Source: K232356 p.7
Power per emitter
5 mW ±20%Source: K232356 p.7
Total optical power
410 mWMatches 82 diodes × 5 mW, so a reader can check it against the two figures in the filing.Source: IEC 60825-1 report supplied by the brand
Illuminated area
348 cm²Source: IEC 60825-1 report supplied by the brand
Irradiance
1.18 mW/cm²average, not per-pointMeasurement distance declared: 100 mm.The 100 mm comes from the IEC 60825-1 test geometry, which is a laser safety classification standard, not a treatment geometry. A cap is worn resting on the head. The brand explicitly stated that it is not established that this is the measurement used to derive the average, so the two figures are NOT equivalent and must not be presented as if they were.Source: IEC 60825-1 report supplied by the brand
Energy density
2.12 J/cm² per sessionSource: IEC 60825-1 report supplied by the brand
Protocol
30 min × 3/week × 16 weeksSource: K232356 p.7
Clinical data
The filing provides no clinical data: substantial equivalence rests on bench testing. Source: K232356.Source: K232356

Do the published numbers agree?

These checks compare figures the manufacturer published against each other. Nothing here is estimated: every operand is a published number and the arithmetic is shown so you can redo it. When a check does not agree, that does not say which figure is wrong — only that they cannot all be right at once.

Numbers agree

Average irradiance vs. total optical power ÷ illuminated area

410 mW ÷ 348 cm² = 1.178 mW/cm² · declared 1.18 mW/cm²

Not enough published data to check

Claimed runtime vs. battery energy ÷ rated power

Missing: battery capacity, battery voltage, rated power, claimed runtime.

Physical upper bound

Average irradiance over the illuminated area cannot exceed total optical power divided by that area, under any measurement geometry — moving a sensor closer or further redistributes light, it does not create power.

410 mW ÷ 348 cm² = 1.178 mW/cm²

derived — calculated here from the two published figures above, not a value the manufacturer states. It bounds the average: a point directly under a diode can be much higher.

Alongside the published literature

ParameterThis deviceRange reported in literature
Wavelength650 nm6501200 nm
Fluence2.12 J/cm²110 J/cm²
Power density1.18 mW/cm²390 mW/cm²

Source: Review of low-level laser therapy in androgenetic alopecia (JCAS). These are the parameters of the devices most often used in the studies reviewed. They are not efficacy thresholds and have not been validated as such. The photobiomodulation response is also biphasic — small doses stimulate and large doses inhibit — so a value above a range is not “better” either.

How we review devices · Device index · FDA filing K232356