Intense Pulsed Light (abbreviated IPL) is a type of light treatment that is non-ablative. This means that the light does NOT remove the superficial layers of skin.
Some lasers, on the other hand, are ablative (remove the outer layers of skin, which is known as resurfacing).
IPL light works by channeling heat at color targets in different layers of the skin. And because it can reach different depths of skin, it can treat a variety of skin conditions.
The major ones are pigmentation, vascular conditions, hair removal, and to a lesser extent collagen production.

PIGMENTATION

Pigmentation means the coloring of the skin. You are born with a certain pigmentation (your natural skin color). But you may have spots or sections of your skin with the darker color or lighter color.

IPL photorejuvenation machine  (and laser) are used to treat hyperpigmentation, which is when you have an excess of pigmentation. In other words, when something is darker than the surrounding skin.
IPL cannot be used to treat hypopigmentation (when you have a spot that is lighter than the surrounding skin).
Here are the types of hyperpigmentation that can be treated by IPL:
sunspots (brown spots due to UV damage)
brown discolorations
acne scars
melasma
birthmarks
actinic keratosis
The light is attracted to a colored target in the skin (say a brown spot). In fact, the darker the spot, the better.
IPL is ideal when there is more contrast between the base skin color and the target color. So for example, a dark spot on the fair skin will be easier to treat because there is a greater color contrast between the skin and the spot.

REDNESS & VASCULAR LESIONS

red blood lines 0719 - What Problems Does IPL Treat?

Vascular is defined as blood-related. A vascular lesion is a problem due to a disruption of the blood vessels. Vascular lesions are red or purple in color.

IPL machine can treat these types of blood-related issues:
rosacea
telangiectasia
spider veins
varicose veins
port wine stains
bruises
and others
Some of these issues may be better treated by laser, depending on the size of the area to be treated, and the depth of the lesion.

HAIR REMOVAL (REDUCTION)

The way you get rid of hair is by destroying the pigment in the hair follicle. The hair follicle is the shaft where a strand of hair is anchored.
The light from IPL (or laser) is attracted to the color of the hair (its pigment).
To destroy the pigment, you need focused heat in the hair follicles. A laser is more effective at delivering focused heat than IPL because it produces a narrow, concentrated beam of light.
So while IPL and laser can both be used to reduce hair growth, a laser is more effective at it. But it comes with considerably more pain and takes more time.
The best candidates for hair removal is darker hair. Light colored hair, such as blonde hair, as well as gray/white hair, cannot be treated since the hairs lack the pigment to attract light.
Just as it is so for pigmented spots, the greater the contrast between the base skin color and the hair color, the better the results. So, dark hair on the fair skin can be removed most successfully.

COLLAGEN PRODUCTION

Another use for IPL light is reducing fine lines and wrinkles and skin tightening. This application is sometimes marketed as “skin rejuvenation,” a vague term that can mean anything today.
The heat from the light stimulates collagen production (by stimulating fibroblast activity), but this does not yield immediate, visible results. You won’t see any “wow” effect after a single treatment. Any changes will be gradual and require a series of treatments.
In general, longer wavelengths and ablative lasers are more effective at treating wrinkles.

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