Glossary of beauty-equipment terms
Short, practical definitions of the terms you hear in laser hair removal, HIFU, RF microneedling, IPL/BBL and CO₂ laser training — plus a one-table comparison of the technologies.
The glossary covers 27 terms: technologies (HIFU, SMAS, RF microneedling, IPL, BBL, lasers), physics (chromophore, wavelength, fluence) and safety (phototype, qualification, test patch, contraindications).
Technologies compared at a glance
| Technology | Energy type | Main target | Typical use |
|---|---|---|---|
| Hair-removal laser (diode, alexandrite, Nd:YAG) | single-wavelength light | hair melanin | hair removal |
| IPL / BBL | broadband light with filters | melanin, haemoglobin | hair removal, vessels, pigmentation, photorejuvenation |
| RF microneedling | high-frequency current via needles | dermis around the needles | skin density and texture, acne scars |
| HIFU (SMAS) | focused ultrasound | points at 1.5–4.5 mm depth | lifting of the jawline and areas |
| Fractional CO₂ laser | light at ~10,600 nm | water in tissue (ablation microzones) | scars, texture, photodamage |
| Q-switch / picosecond laser | very short pulses | pigment particles | tattoo and PMU removal |
Terms
Educational material; it does not replace the device instructions, client qualification or legal requirements.
Ablative and non-ablative laser
An ablative laser removes (vaporises) a layer of tissue and therefore needs healing time — for example CO₂. A non-ablative laser heats tissue without removing it, with a shorter recovery.
Absolute and relative contraindications
Absolute ones rule out a procedure whatever the parameters (for example an active infection in the area). Relative ones call for postponing, changing parameters, a test patch or medical consultation.
Alexandrite laser
A laser of about 755 nm, strongly absorbed by melanin. It works quickly on light to medium skin; on tanned or dark skin the risk of pigmentation rises.
BBL
BroadBand Light — the trade name of Sciton's IPL platform. Every BBL is an IPL, but not every IPL is a BBL.
Chromophore
A structure or substance that absorbs light of a given wavelength: melanin in hair, haemoglobin in vessels, pigment in a tattoo.
Client qualification
Assessment before a procedure: interview, indications and contraindications, phototype, skin condition, medications. It ends in a decision — proceed, postpone or refer to a doctor — and its documentation.
Contact cooling
Cooling the skin through a sapphire, plate or chilled handpiece before, during and after the pulse. It protects the epidermis and allows the energy the target needs to be delivered safely.
Diode laser
A semiconductor laser, usually around 800–810 nm, the most common in hair removal. Well absorbed by melanin and versatile; on darker skin it needs careful parameter selection.
Erythema
Redness of the skin after a procedure. Mild and short-lived it can be an expected reaction; marked or lasting redness is a signal to change parameters or seek consultation.
Fitzpatrick phototype
A classification of skin I–VI by reaction to sun, from always burns (I) to never burns (VI). One of the factors in qualifying a client for light-based treatments.
Fluence
The energy delivered per unit area, in J/cm². Together with pulse duration it sets the strength of the effect; too high raises the risk of a burn.
Fractional CO₂ laser
A laser of about 10,600 nm acting on water in tissue. It splits the beam into microzones of ablation with healthy skin between them; used for scars and photodamage, among others.
HIFU
High-Intensity Focused Ultrasound — ultrasound focused into a point at a set depth (for example 1.5, 3.0 or 4.5 mm). It heats tissue at that point without disturbing the skin surface; used for lifting and firming.
HIFU cartridge
A replaceable applicator of a HIFU device with a specific focal depth and size. Choice depends on the area, tissue thickness and treatment goal; a wrong choice increases the risk of complications.
IPL
Intense Pulsed Light — broadband pulsed light. Instead of a single wavelength it emits a wide spectrum from which filters cut the required range; used for hair removal, vascular and pigmentation concerns.
Melanin
The pigment of skin and hair, the main chromophore in hair removal and light treatments. The more melanin in the epidermis, the higher the risk that energy is absorbed at the surface.
Nd:YAG
A neodymium laser of 1064 nm (and 532 nm in some uses). It penetrates deeper and is less absorbed by epidermal melanin, so it is chosen for darker phototypes and in tattoo removal.
Picosecond laser
A laser that generates pulses in the picosecond range — even shorter than Q-switch. It shatters pigment photoacoustically; used in tattoo removal and pigmentation concerns.
PIH — post-inflammatory hyperpigmentation
Dark patches after irritation or injury to the skin. More common in higher phototypes and after tanning; one of the main risks of energy-based treatments.
Pulse duration
The length of a single pulse (from nanoseconds to milliseconds). It is matched to the size of the target, its thermal relaxation time and the phototype.
Q-switch
A technique that generates very short, powerful pulses (nanoseconds). It fragments tattoo or PMU pigment particles, which the body gradually clears; typical of Nd:YAG and alexandrite lasers.
RF microneedling
Radiofrequency microneedling — high-frequency current delivered through fine needles inserted into the dermis at an adjustable depth. It heats tissue around the needles, improving skin density and texture.
Selective photothermolysis
The principle described in 1983 by Anderson and Parrish: light absorbed by a chosen target (chromophore) heats it with a short pulse before the heat spreads to its surroundings. The basis of hair removal, vascular treatments and tattoo removal.
SMAS
The superficial musculoaponeurotic system of the face — the layer connecting facial muscles to the skin. It is the target depth of HIFU lifting; it lies deeper than the dermis, so working on it requires knowledge of anatomy.
Test patch
A treatment on a small, inconspicuous area and assessment of the skin's reaction after a time appropriate to the technology. It complements the interview with the skin's real response to the chosen settings.
Thermal relaxation time
The time in which a structure loses half of its accumulated heat. A pulse shorter than this time heats the target, not its surroundings; larger targets (a hair follicle) tolerate a longer pulse than tiny ones (pigment particles).
Wavelength
The property of light (in nanometres) that determines what absorbs it and how deep it penetrates. Shorter wavelengths are absorbed more strongly by epidermal melanin, longer ones penetrate deeper.
Want to see it in practice?
In OG Academy training we move from definitions to supervised work on models.