What is better?? 10ms or 3ms and why??

Hair Removal Methods Laser hair removal
#1

Could somebody be kind enough and explain this to me :frowning: ?

#2

I am reading and this came up.

“Do NOT ignore this advice! If you say your hair is thick, use 20ms or max, 10ms. NOT 3ms.”

So if you have thick coarse hair you should use higher ms??

Any experts want to chime in??

#3

Pulse width is exactly what it sounds like – it’s the length of time between pulses of the laser. So the laser fires, but it fires multiple pulses at a time and the time between those firings is the time listed. So 3ms means the time between the pulses is faster. That’s usually the lowest a machine can go, so the goal is that it heats up the hair quickly and prevents the hair from “cooling down”. So lower pulse width makes it more likely to kill the hair – on darker skin however, that low pulse width tends to be a lot less safer since it’ll be heating up the skin surrounding it too. That’s why generally 20ms is the lowest recommended setting on darker skin

#4

I was under the impression Hertz was the amount of pulses.

1hz= 1 pulse per second
1.5hz = 1.5 pulse per second
2 hz= 2 pulse per second.

Pulse width or duration selection is dependent on the TRT, or thermal relaxation time of a structure. When treating hair, you should notice that hairs will have different diameters. The greater the diameter, the longer the thermal relaxation time, thus the longer pulse duration being required.

In other words

3 ms finer hair
10 ms is thicker coarser hair

That is why most start at 20 ms or 10 ms the first couple of treatments and then go to 5ms or 3 ms as hair becomes thinner.

I guess I just answered my question but I did read up after I posted and wanted to share the results.

#5

I suppose what I wrote was slightly confusing in that regard. Hertz is how quickly the laser is allowed to fire. The pulse width determines how quickly the area gets heated. When the laser fires, it’s not just one blast but several spaced so many milliseconds apart.

Most laser techs I’ve been to start at the lowest possible pulse width for pale skin, not “working their way down”

#6

Brenton, what you’re talking about is ‘multiple synchronized pulsing’ described here. Pulse width is the time the laser is ON, not the time between pulses. Some laser models use only one pulse, while others use 2 to 5 successive pulses where each pulse is on for “pulse width” ms, then off for a longer delay. In this image, pulse width is 5ms, delay is 20ms.

But you are correct that pulse width determines how quickly an area is heated. My understanding is at any particular setting, say 10J, the 10J of fluence is spread over the pulse width. Whether pulse width is 3ms or 20ms, you still only get 10J of fluence delivered, but at 20ms the energy is delivered more slowly. Spreading the energy over a longer time period helps let skin cool while the hair heats up. Hairs tend to both heat and cool more slowly than skin, especially coarse hairs.

The Hz setting on some machines refers to how quickly the entire treatment is repeated. So a setting of 1 Hz would repeat the 2-5 pulses of 5ms on, 20ms off every 1 second for as long as you hold the trigger down. I assume that feature is useful for experts who can hold the trigger and cleanly move the target to the next spot to treat every second. I don’t understand why machines go up to 10Hz (10 treatments per second) because I can’t see anyone being able to move the target so quickly with any accuracy. I guess maybe if you just slide it down a leg at a very precise speed then the 10Hz setting might roughly work out.

#7

There are things to consider, principally:

– Wavelenghts (nm)
The laser wavelength for deep, thick & dark hair roots should be 1064nm (Nd:YAG); but it won’t be effective for shallower hair roots.
The laser with wavelength of 755 nm (Alexandrite) & 800-900 nm (Diode) work effectively with shallower, thinner & lighter hair roots.
Many IPLs & Lasers with other wavelengths do not work effectively to retard hair growth. So before you pay, ask the therapist what wavelength they use to remove your hairs? Because if your hairs root deeply, energy form lasers & IPLs with shorter wavelengths won’t reach your hair roots; vice versa shallower hair roots won’t respond well to lasers with longer wavelengths

– Skin colours
Nd:YAG is suitable for all skin types, but Alexandrite & Diode are safe to be used for Fitzpatrick Skin Type 1, 2 & 3 only.
Very dark-skinned individuals need to have a laser with a longer wavelength. The longer wavelength is needed so as not to have the laser energy preferentially absorbed by the top layer of skin as would occur with the shorter wavelength laser. The longer wavelength penetrates deeper and will target the deeper dark pigment decreasing the risk of blisters or burns on the surface.

– Natural Hair Colours
See => https://www.facebook.com/upweylaser/posts/586060421734589

– Density & diameter your dark hair roots
The treatments are most effective on dense, thick, coarse & dark hair roots because they have a lot of pigment and can absorb a lot of heat. Sparse, fine hairs cannot absorb much heat. Thus, LHR lose efficacy on very thin or vellus hairs.

– Pulse Duration
Laser devices operate as continuous wave or pulsed systems (e.g. single or repetitive‑pulsed lasers). Examples of multi-pulsed (in other word, repetitive-pulsed) laser devices are Short Pulsed, Long Pulsed and Q-switched for different treatment purposes. But long-pulsed lasers in 755, 800-900 & 1064 nm have proved to be effective to reduce hairs permanently.

Q-switched & other short-pulsed lasers which emit much shorter pulses won’t do anything to your hairs except bleaching hair colors. Both the amount, density & size of your hairs will remain exactly the same. Remember! Once hair roots get bleached, IPL & Laser won’t work on lighter hairs 😭.

( http://www.bodylanguage.net/thermal-relaxation-times/ )

– Fluence (J/cm^2), Spot Size (mm) & Repetition Rate (Hz) to be applied are according to different recommendations among different brands.
In general, the smaller the spot size the higher the fluence.
Settings can be increased or decreased depending on the previous results and clients’ feelings during different sessions.
Rule of thump: Look for perifollicular edema which should appear few minutes after firing

– Phase of the hair growth cycle
Laser & IPL can only target the anagen.

At any given time, not all hairs are in the anagen phase.Therefore, multiple treatments are required to achieve the optimal appearance.

Timing between treatments is very important for optimal results with laser hair removal. It is important to pay for treatments one by one vs paying for packages of laser services up front. Different areas of the body have different hair growth cycles. In order to catch the most hair in the active cycle (or anagen phase) during your laser hair removal sessions, treatments should be scheduled according to the hair growth cycles.

In general, the best way to approach this is to use the regrowth of hair in the treated area as your guide… in other words, when a significant percentage of the hair starts growing back, return for the next treatment.
It could be as short as 4-6 weeks on the face, and as long as 8-12 weeks (or longer) for the legs. Bikini, chest, back, underarms, stomach etc. should be scheduled every 6-8 weeks, as for examples. These are different among different individuals.

Typically 6-8 sessions for each certain body area are recommended to catch each cycle of hair growth, although some people may be satisfied with their results sooner. Some may require more sessions. Following these guidelines should result in the greatest reduction of hair.

However, once desired results are achieved, many people come back annually for 1-2 treatment maintenance sessions. While in the maintenance phase, the ideal time to get a touch-up session is when you notice there are times when hair growth seems to be more aggressive. This is, as hair in the active growth phase is most effectively targeted.
Another recommended alternative would be to START WITH LASER treatment. Multiple laser sessions will be required. Once desired results are achieved by laser, then you may choose to FINISH WITH ELECTROLYSIS. This is the fastest way to achieve the optimal appearance (be it total removal or just thinning of the hair).

#8

Your question is regarding how long each laser shot/firing is allowed to work on you. There are few terms for this meaning such as Pulse Duration or Pulse Width. The longer pulse duration is for the thicker/bigger hair diameter. Longer pulse shouldn’t be used for thinner hairs to prevent damage to adjacent tissue

#9

Don’t some laser machines have fixed pulse widths…like 3 or 5ms? Would that make them less effective on thicker hair?

#10

Hi Joben,

Pulse width isn’t the only setting parameter of the laser device.

#11

What do you mean?

#12

Hi Joben,

The pulse width isn’t the only setting parameter, there r fluence & repetition of the firing of laser pulses (Hz) in order to raise the temperature of hair shaft & the colourless follicle upto the degree that can coagulate them. Nothing beat the simple basic fact (scientific knowledge)

#13

I know, but in your previous post you said “Longer pulse shouldn’t be used for thinner hairs to prevent damage to adjacent tissue.” If a machine has a fixed pulse width of 3-5ms (versus an adjustable pulse width) wouldn’t that make the machine unsuitable for thinner hairs?

#14

Hi Joben,

Since Fluence can’t b compared among different brands of laser devices so some brands require only 3-5ms. Some brands required 60-80ms for lower fluence to work longer.

#15

So please read my rule of thumb & this =>

#16

I read that post that you linked above and I agree with everything you wrote. The problem is finding a good laser tech that will actually use high enough settings. I’ve had LHR a few times and all but once I’m usually pleading with the tech to use more aggressive settings.

#17

Good article Melb Aussie!

Although I’ve not had the opportunity, I’ve thought about the way therapists often combine electrolysis and laser: “laser first and then follow-up with electrolysis.”

I’d do the reverse: One fast clearance with electrolysis (body hair with local anesthetic … to go super-fast) and then, when the hairs return in a couple months (all in anagen); then laser.

In this way, the laser would be targeting only anagen hairs AND they would be nicely thinned-out (say at least 50% reduction) so that higher laser energy could be used without causing too much pain. I don’t know if anyone has tried this; I would. (The “catch” of course is the requirement for a very fast body technique … cleared-off in a couple day’s work … and local anesthetic.)

#18

Honestly, if I found an electrologists who could work fast enough to do a body clearing in a few days with local anaesthetic, I would be continuing with that electrologist for subsequent clearings despite the higher cost and time commitment (in terms of hours spent with the electrologist).

At that point, I’d be too concerned about elongating the process by introducing laser. Even though the hairs treated would be anagen, a considerable amount probably wouldn’t respond effectively to laser, but they would still shed from the follicle and I would have to wait for their cycle to return.

I might save money, but it would be at the cost of elongating the whole treatment by a year maybe. Perhaps my understanding is flawed, so please feel free to correct me.

I did laser first anyway, and now electrolysis, and I’m pleased with the results of both, and more so the results of electrolysis. I still have laser done on areas that I can’t yet treat with electrolysis due to time and money. I doubt I’ll receive any more permanent results from laser, but the temporary result is far better than waxing and the cost is about the same when considering I can wait longer between laser appointments.

#19

Hi Joben,
Please note that the “rule of thumb” won’t appear as soon as the laser beam/pulses hit you, but few minutes or longer after that => That’s one of the reasons to do the test patching to find the right energy for different individuals.
Make sure you don’t feel the heat (u may still feel warm a second or 2) as soon as the laser pulses moved away from that treated area. The heat should go away as soon as the pulse moved away from that treated spot => Otherwise burn.

To my dear & well respected Michael,
I’m looking towards for training until you have got better & gain back your health & strength. So that I’ll trial & error your proposal.

Hi Scurvy, I’m working on it in order to gain faster speed with my Electrolysis Skills.

#20

Might be up for some “experimentation” as my eye “sinks slowly in the West?” Got a client in Adelaide and Melbourne … ready for the third pass (and the long flight over here). I’ll do some emailing to the “dudes,” … “mates?” … “blokes?”

Hairy backs …

Eye surgery on Tuesday, if I don’t chicken-out (I want to). A gross procedure with high risk. I mean, I’m happy to be a one-eyed pirate (“hee-yarrr”); but a one-eyed electrologist probably wouldn’t be advisable. “Cyclops-electrology?” “the Braille Institute of hair removal?” Ugh!