As you know different colored surfaces either absorb or reflect light. Red pigment absorbs green light so I think it is a matter of duration and power. If I were to point a strong green laser at a red balloon the balloon would explode but it probably would not rupture a green or a white balloon as quickly if at all. It certainly would pop a black balloon.
As to the FDA, they are the most untrustworthy agency to ever come down the pike. What they say is safe often isn't and what they say is unsafe often isn't either. They are not there to protect anyone but medical corporations.
There are hair removal lasers and light systems for sale to the general public that used pulsed light the same as what medical offices used but customers don't get the results promised and often these units arrive not working at all. Also, quality control is not good and some may be too powerful and others may be weak and ineffective and the FDA has no jurisdiction as to their safety or efficacy. That would fall on the FTC which does a lousy job protecting consumers same as the FDA does a lousy job protecting medical consumers. The FDA is an industry lapdog and not the citizen's watchdog people think it is.
It seems to me that a class 3R laser would not present much of a hazard especially if I used eye protection and stop the exposure when I feel a sting.
I borrowed a friend's laser for pain and it worked pretty well. If you didn't keep it moving you would feel a burn but it worked on pain. Chiropractors and physical therapists are starting to use them.
There is no way I would use a class 4 because they can burn things very quickly.
905 nm and 980 nm is best absorbed by hemoglobin.
I see it like this. Sparks for a sparkler are very high in temperature but are low in BTUs that the sparks can land on your skin and not cause damage. Also, I'm thinking that ablation of the hair follicle will occur much like a laser popping a balloon within a balloon or lighting a match within a balloon without damaging the balloon.
No you need high energy pulses to remove the follicles. There is a reason why they have special machines to do it. They pulse the laser so that the exposure time is enough for the follicle but not the skin. By using a CW laser, you will be burning more than just the follicle or nothing at all if you are not using a high enough power laser. You are right on the absorption, but incorrect on the analogy of popping a balloon. Don't base your distrust of FDA as a reason to risk your health. If I started mislabeling objects as fatal weapons, would you test it to find out. :thinking: In this case, they are not over/under exaggerating. And again, please stop shining lasers onto your skin. If a 3R laser is producing a burn then it is not a 3R, it is actually a 3B. 5mW and under is not enough power to burn on its own. The laser is over 5mW for this, hence is now in the Class 3B category.
No you need high energy pulses to remove the follicles. There is a reason why they have special machines to do it. They pulse the laser so that the exposure time is enough for the follicle but not the skin. By using a CW laser, you will be burning more than just the follicle or nothing at all if you are not using a high enough power laser. You are right on the absorption, but incorrect on the analogy of popping a balloon. Don't base your distrust of FDA as a reason to risk your health. If I started mislabeling objects as fatal weapons, would you test it to find out. :thinking: In this case, they are not over/under exaggerating. And again, please stop shining lasers onto your skin. If a 3R laser is producing a burn then it is not a 3R, it is actually a 3B. 5mW and under is not enough power to burn on its own. The laser is over 5mW for this, hence is now in the Class 3B category.
Thanks Radim. No worries, sometimes I can give the same person rep within a few days, but then at times it can take a whole week. I can't remember how many it is you have to give out in order to re-rep someone. :beer:
BTW: Regarding graphic art, I forget to mention also Brucemir's artworks - amazing indoor beamshots, very creative IMO. Here for example. Also you might check ArcticDude's thread here.
No you need high energy pulses to remove the follicles. There is a reason why they have special machines to do it. They pulse the laser so that the exposure time is enough for the follicle but not the skin. By using a CW laser, you will be burning more than just the follicle or nothing at all if you are not using a high enough power laser. You are right on the absorption, but incorrect on the analogy of popping a balloon. Don't base your distrust of FDA as a reason to risk your health. If I started mislabeling objects as fatal weapons, would you test it to find out. :thinking: In this case, they are not over/under exaggerating. And again, please stop shining lasers onto your skin. If a 3R laser is producing a burn then it is not a 3R, it is actually a 3B. 5mW and under is not enough power to burn on its own. The laser is over 5mW for this, hence is now in the Class 3B category.
I could be wrong but my guess is OP is a troll trolling with lack of knowledge and ability in many areas, and suggesting reckless brain damaged behaviors --either way a person's intelligence and common sense are evidenced by the person's actions.
Attempting to reinvent laser hair removal with laser pointers is simply profoundly stupid and unnecessary. Laser hair removal has been practiced with mixed ressults since 1997 and experimentally for 20 years before that. At best it is a medical procedure that requires proper equpiment, training to perform, and carries potential risks. It can be dangerous in inexperienced hands even with the proper equpiment. Burns, permanent changes to your skin color, and scars can occur. The knowledge and experience base about it is a bit larger than the daydreams someone with a laser pointer, very minimal knowledge, and no experience.
Thanks Encap. Good points yourself. :beer:
I'm concerned that he is going to go ahead with it anyway. So a disclaimer. LPF in no way endorsed this project and others should not follow suit. Shave, grow a beard or get professional treatment. Either one will do.
No you need high energy pulses to remove the follicles. There is a reason why they have special machines to do it. They pulse the laser so that the exposure time is enough for the follicle but not the skin. By using a CW laser, you will be burning more than just the follicle or nothing at all if you are not using a high enough power laser. You are right on the absorption, but incorrect on the analogy of popping a balloon. Don't base your distrust of FDA as a reason to risk your health. If I started mislabeling objects as fatal weapons, would you test it to find out. :thinking: In this case, they are not over/under exaggerating. And again, please stop shining lasers onto your skin. If a 3R laser is producing a burn then it is not a 3R, it is actually a 3B. 5mW and under is not enough power to burn on its own. The laser is over 5mW for this, hence is now in the Class 3B category.
The follicle is below the skin so the light has to penetrate the skin without damaging it. Right? Would it not be like a laser beam going through glass and not heating the glass but heating what is behind the glass.
I think the medical hair removal laser are pulsed because they fire a wide beam to treat several hairs at one shot and the pulses are controlled in their intensity or perhaps the duration of the pulse like a photographic strobe. I believe in photography the pulse is controlled by duration.
A watched a laser enthusiast on youtube measuring laser imported from China and it seems that the Chinese deliberately mislabel the power so that they can sneak them past regulations.
From what I got from the video is that some laser pointers are more powerful than what the labels say they are.
As I said in my intro, my interests include medical and that got me thinking that maybe lasers can be used in acupuncture in place of moxa cautery. Then I found this very informative article. A Guide To Cold Lasers for Acupuncture and Trigger Point Therapy
It comes down to joules. Theoretically and assuming tissue does not dissipate heat the duration of a laser beam on a surface that absorbs that beam, that surface that tissue will have an increase in heat and temperature. Based on what I have read 500mW depending on the color of the light and the color of the surface, it can cause burning.
I just read that hair removal lasers use around 12 joules per square centimeter and can exceed 30 J/cm2 without much skin damage.
It comes down to joules. Theoretically and assuming tissue does not dissipate heat the duration of a laser beam on a surface that absorbs that beam, that surface that tissue will have an increase in heat and temperature. Based on what I have read 500mW depending on the color of the light and the color of the surface, it can cause burning.
This doesn't make a whole lot of sense ... <500mW can cause burning depending on the wavelength and skin colour.
I just read that hair removal lasers use around 12 joules per square centimeter and can exceed 30 J/cm2 without much skin damage.
J/cm² isn't enough information alone, you need to know pulse duration. 30 joules over 300 seconds is 0.1W, while 30J over 0.0003s is 100,000W, the resultant damage from the latter would be far worse than from the former.
Again, this is not something you should be attempting yourself, especially with no knowledge (or almost no knowledge) of lasers, or for that matter dermatology.
He's not listening, I'm going to just observe this thread from now on. How many more people do you need to say that it isn't a good idea and to leave it up to the professionals?
Am I paranoid or is it trolling?
Diachi explained you basically what pulsed laser is in terms of energy (or energy density) and power.
Maybe you could say what is the purpose? To get hair removed or reinvent what is invented already?
There is some reason why it took such a long time to get laser hair removal comercially available - let's call it research and developement. I bet they tried many potentialy suitable lasers based on best scientific knowledge availabile and only a few methods got to the real application. Testing something like this on yourself without significant research not only in laser technology but in dermatology and other areas is pure hazarding with your health. Even tested methods with great experience do not work to everybody as everybody is slightly different, therefore even the application is highly individual and the specialist performing the application has to be educated and with experience - again there is a reason for that why you do not find really working consumer device for that.
I think you got the best advices here. However if you have questions about why this and that cannot be done, ask. But please do not make it seem you want to get some advice how to make some laser hair removal device from lasers which are designed for different purposes.
I agree 100% it is not a good idea and the OP should not attempt it for all the reasons everyone has already stated.
If he goes ahead with the hairbrained scheme (no pun intended), I would like to see the before , druring and after pictures---will be like an new episode of Jackass the movie and TV show, more than likely.
Think of the potential hazard of shaking a little and hitting your eye.. anything with enough power to burn objects to your eye with or without goggles is a chance I'd not be willing to take, just my $0.02. I like the laser painting though if proper PPE + precautions are taken each time.
Think of the potential hazard of shaking a little and hitting your eye.. anything with enough power to burn objects to your eye with or without goggles is a chance I'd not be willing to take, just my $0.02. I like the laser painting though if proper PPE + precautions are taken each time.
Safety protocol including using PPE is absolutely necessary for laserpainting. No exception. There is a very little room for error. Especially in outdoor environment a lot of factors have to be considered. And if laser composition setup is complicated in terms of many beams of various wavelengths when you need to switch eye protection as you move between the beams, then it takes a lot of concentration during exposure and preparation like finding safe zones, where you can switch glasses or do the painting. If you have glasses all the times you won't see the scene in night, so safe distance is needed from dot as well as considering scene being painted and careful examination for anything reflective (piece of glass, nail, reflective sign...) Sometimes I need to paint with higher power (let's say class 4) laser in close range then you need to prepare it and paint with glasses on - it is painfully bright and dangerous to observe dot in close range. Or when you set the optics - glasses on as reflection might occur and occurs in reality, I can see it through glasses clearly. Important when painting near sphere is to have still hand and think even more before you move it, otherwise you might get reflection in your eye. So far I've had no accident, just minor errors which I learn from to improve safety protocol. Every error I do I say myself: "Stupid idiot, what if... Why don't you think about it before?" But really I'm very happy to learn from it and improve. You gain a lot of respect when doing experiments with lasers and if you can see what they are able to do. The worst I experienced was a very short lasting afterimage from bright dot, but afterimage from camera flash or my flashlight reflected from close tree lasts much longer. I also check my sight reguraly by Amsler grid and evaluate the effects according to laserpointersafety.com procedures to consider any potential damage - not occured so far. Also the blue light hazard for certain wavelengths is necessary to consider. You do not want to get close to a blue dot without glasses. And I'm not mentioning here safety procedures to be taken to make the laserpainting safe for enviroment around and camera... Special chapters.
The follicle is below the skin so the light has to penetrate the skin without damaging it. Right? Would it not be like a laser beam going through glass and not heating the glass but heating what is behind the glass.
What? I do recall correctly you saying that when you shine a laser on your skin you feel a stinging burn right? So you kind of disproved your point by your own findings. :banghead:
I think the medical hair removal laser are pulsed because they fire a wide beam to treat several hairs at one shot and the pulses are controlled in their intensity or perhaps the duration of the pulse like a photographic strobe. I believe in photography the pulse is controlled by duration.
Again, the idea is to pulse the laser so it burns the follicle before the skin is affected. Are your lasers engineered to be at the right pulse rate and energy. The answer is no, so they are not going to work well for your application. They are just going to lead to skin burns and very little damage to the hair follicles completely missing the point of why you did it in the first place.
A watched a laser enthusiast on youtube measuring laser imported from China and it seems that the Chinese deliberately mislabel the power so that they can sneak them past regulations.
From what I got from the video is that some laser pointers are more powerful than what the labels say they are. Yes, those cheap pointers often are. They often emit harmful amounts of IR as well. Don't point them at eyes or skin.
As I said in my intro, my interests include medical and that got me thinking that maybe lasers can be used in acupuncture in place of moxa cautery. Then I found this very informative article. A Guide To Cold Lasers for Acupuncture and Trigger Point Therapy
I'm not even going to bother.
It comes down to joules. Theoretically and assuming tissue does not dissipate heat the duration of a laser beam on a surface that absorbs that beam, that surface that tissue will have an increase in heat and temperature. Based on what I have read 500mW depending on the color of the light and the color of the surface, it can cause burning.
I just read that hair removal lasers use around 12 joules per square centimeter and can exceed 30 J/cm2 without much skin damage.
Diachi already done a good job on this one. Pulse duration is critical and what you are saying doesn't make much sense to me either.
I didn't have time to deal with this properly yesterday. See answers in red.
Please for the final time, see a professional about this before you come back on here with a new thread:
CO2 Lasers and Scar Removal Theory
After my previous experiment, I have now got facial scarring over my face and am still growing a beard. I heard about CO2 lasers being used to remove the effect of scarring. Should I go for a 50W or an 80W tube to do the job?
After my previous experiment, I have now got facial scarring over my face and am still growing a beard. I heard about CO2 lasers being used to remove the effect of scarring. Should I go for a 50W or an 80W tube to do the job?
Good points yourself. :beer:
... <500mW can cause burning depending on the wavelength and skin colour. 
op: