142
There are two methods for applying high-frequency current.
1. Direct surface application. Do not apply any product to the client’s
face. If the glass electrode is hard to move on the skin, use some gauze over
it. The cosmetologist holds the handpiece, where the glass electrode is inserted, and applies it directly to the client’s skin, moving it slowly over the
entire face for stimulation (Figure 7–11). When applying and removing
the electrode from the skin, you must hold your finger on the glass electrode to prevent sparking. Remove your finger once the electrode has been
placed on the skin. Dab the electrode on a spot to cause sparking, which
helps disinfect and heal acne and other lesions.
Figure 7–11
application.
Direct high-frequency
2. Indirect application. The client holds the tube electrode (with
the metal coil inside) while you massage the face with your hands (Figure 7–12). At no time should you hold the electrode. To prevent shock,
turn on the current only after the client has firmly grasped the electrode. Turn the current off before you remove the electrode from the
client’s hand. The indirect application stimulates all cell functions without the irritation that could occur with direct application. This treatment is beneficial for sensitive, dehydrated skin.
LIGHT THERAPY
Figure 7–12
application.
Indirect high-frequency
7
Long wavelength
Light therapy refers to treatment by means of light rays. Light or electrical waves travel at a tremendous speed–186,000 miles per second. There
are many kinds of light rays, but in esthetics work we are concerned with
only three–those producing heat, known as infra-red rays; those producing chemical and germicidal reaction, known as ultraviolet rays, and visible light, all of which are contained within the spectrum of the sun.
If a ray of sunshine is passed through a glass prism, it will appear in
seven different colors, known as the rainbow, arrayed in the following
manner: red, orange, yellow, green, blue, indigo, and violet. These colors,
which are visible to the eye, constitute the visible rays.
Scientists have discovered that at either end of the visible spectrum are
rays of the sun which are invisible to us. The rays beyond the violet are the
ultraviolet rays, also known as actinic rays. These rays are the shortest and
least penetrating rays of the spectrum. The action of these rays is both
chemical and germicidal. Beyond the red rays of the spectrum are the infrared rays. These are pure heat rays.
Low
frequency
High
frequency
Short wavelength
Figure 7–13
wavelengths.
Long and short
Part 2
General Sciences
Visible light is electromagnetic radiation that we can see. Electromagnetic radiation, also called “radiant energy,” carries, or radiates, energy through space on waves. These waves are similar to the waves caused
when a stone is dropped on the surface of the water. The distance between
two successive peaks is called the wavelength. Long wavelengths have low
frequency, meaning the number of waves is less frequent (fewer waves)
within a given length. Short wavelengths have higher frequency because
143
ibl
es
pe
ctr
um
RED
ORANGE
Visible heat rays
YELLOW
GREEN
Prism
BLUE
INDIGO
Ultraviolet
Shorter wavelength
Higher frequency
Less penetrating
Invisible
(5% of natural sunshine)
Figure 7–14
Neutral
Visible chemical
actinic (cold) rays
35% visible light rays
Vis
Infrared
Longer wavelength
Lower frequency
More penetrating
Invisible
(60% of natural sunshine)
VIOLET
The visible spectrum.
the number of waves is more frequent (more waves) within a given length
(Figure 7–13).
The entire range of wavelengths of electromagnetic radiation (radiant
energy) is called the “electromagnetic spectrum.” Visible light is the part
of the electromagnetic spectrum that we can see. Visible light makes up
35 percent of natural sunlight (Figure 7–14).
Ultraviolet rays and infrared rays are also forms of electromagnetic
radiation, but they are invisible because their wavelengths are beyond the
visible spectrum of light. Invisible rays make up 65 percent of natural
sunlight.
Within the visible spectrum of light, violet has the shortest wavelength and red has the longest. The wavelength of infrared is just below
red, and the wavelength of ultraviolet is just above violet. Infrared and ultraviolet rays are not really light at all. Again, they are the wavelengths of
electromagnetic radiation that are just beyond the visible spectrum.
Therapeutic lamps are used to produce artificial light rays in the salon. These lamps are capable of producing the same rays that are produced
by the sun. Thermal (heat), mechanical, and chemical effects are
3✓
produced by therapeutic lamps.
?
Did y u know...
Over one million new cases of skin cancer are diagnosed each year. It is estimated that one in five Americans will
develop skin cancer, and 90 percent of
those cancers will be the result of exposure to UV radiation from the sun
and from tanning beds.
Ultraviolet Rays
Ultraviolet (UV) rays make up 5 percent of natural sunlight and are also
referred to as cold rays or actinic rays. UV rays have short wavelengths, are
the least penetrating rays, produce chemical effects, and kill germs.
Exposure to the sun can be beneficial if recommended guidelines are
followed. Natural sunlight kills germs and produces vitamin D in the skin.
Chapter 7
Basics of Electricity
7
144
Types of Light
Beneficial Effects
Ultraviolet
increases the elimination of waste products
improves the flow of blood and lymph
has a germicidal and antibacterial effect
produces vitamin D in the skin
can be used to treat rickets, psoriasis and acne
produces a tan
Infrared
heats and relaxes the skin
dilates blood vessels and increases circulation
produces chemical changes
increases metabolism
increases production of perspiration and oil
deep penetration relieves pain in sore muscles
soothes nerves
White Light
relieves pain in the back of the neck and shoulders
produces some chemical and germicidal effects
relaxes muscles
?
Blue Light
Did y u
know...
Over one million new cases of skin cancer are diagnosed each year. It is estimated that one in five Americans will
develop skin cancer, and 90 percent of
Red Light
those cancers will be the result of exposure to UV radiation from the sun
and from tanning beds.
soothes nerves
improves skin tone
provides some chemical and germicidal effects
used for mild cases of skin eruptions
produces little heat
improves dry, scaly, wrinkled skin
relaxes muscles
penetrates the deepest
produces the most heat
7
Table 7–2
Effects of different types of rays used in light therapy.
Ultraviolet radiation can be used to treat rickets (a disease characterized by
soft and deformed bones), psoriasis, and acne. Exposure to UV rays also
stimulates the skin’s production of melanin, which causes a tan and helps
protect the skin from further damage. However, deep tanning is another
matter; although a deep tan may look healthy, it is really a sign that the
skin is under attack from UV radiation.
Although the application of UV rays can be beneficial, it must be
done with the utmost care. Ultraviolet rays are applied with a lamp at a
distance of 30 to 36 inches. The therapy should begin with exposure
times of two to three minutes with a gradual increase in exposure time
to seven or eight minutes. Overexposure to UV rays can produce
Part 2
General Sciences
145
painful burns and blistering, increase the risk of skin cancer, and cause
premature aging of the skin. Never leave your client unattended during
the exposure time.
Infrared Rays
Infrared rays make up 60 percent of natural sunlight. Infrared rays have
long wavelengths, penetrate the deepest, and produce the most heat.
Infrared lamps should be operated at a distance of at least 30 inches,
with an exposure time of about five minutes. Check the comfort of your
client frequently during the service. Never leave the client unattended.
Visible Light Rays
Visible light rays are the primary source of lights used for facial and scalp
treatments. The bulbs used for therapeutic visible light therapy are white,
red, and blue.
White light is referred to as “combination light” because it is a combination of all the visible rays of the spectrum. White light has the benefits of all the rays of the visible spectrum. Blue light should only be used
on oily skin that is bare. It contains few heat rays, is the least penetrating,
and has some germicidal and chemical benefits. Red light is used on dry
skin in combination with oils and creams. Red light penetrates the deepest and produces the most heat. Table 7–2 lists the effects of the dif4✓
ferent rays used in light therapy.
7
Chapter 7
Basics of Electricity
chapter glossary
active electrode
alternating current (AC)
amp (A)
anaphoresis
anode
blue light
cataphoresis
cathode
circuit breaker
complete circuit
Unit that measures the strength of an electric current (the number of electrons flowing through a wire).
Process of forcing liquids into the tissues from the negative toward the positive pole.
Positive electrode.
Therapeutic light that should only be used on oily skin that is bare; contains few heat rays, is the least
penetrating, and has some germicidal and chemical benefits.
Process of forcing acidic substances into deeper tissues using galvanic current from the positive toward the
negative pole.
Negative electrode.
Switch that automatically interrupts or shuts off an electric circuit at the first indication of overload.
The path of an electric current from the generating source through conductors and back to its original source.
Any substance, material, or medium that conducts electricity.
converter
Apparatus that changes direct current to alternating current.
direct current (DC)
electric current
electricity
electrode
electromagnetic radiation
Process used to soften and emulsify grease deposits (oil) and blackheads in the hair follicles; also called
disincrustation.
Constant, even-flowing current that travels in one direction only and produces a chemical reaction.
Flow of electricity along a conductor.
Form of energy that, when in motion, exhibits magnetic, chemical, or thermal effects; a flow of electrons.
Applicator for directing the electric current from the machine to the client’s skin.
Also called radiant energy because it carries, or radiates, energy through space on waves.
electrotherapy
Electronic facial treatments.
faradic current
Alternating and interrupted current that produces a mechanical reaction without a chemical effect.
fuse
galvanic current
inactive electrode
infrared rays
insulator (nonconductor)
146
Rapid and interrupted current, flowing first in one direction and then in the opposite direction.
conductor
desincrustation
7
Electrode used on the area to be treated.
Special device that prevents excessive current from passing through a circuit.
Constant and direct current (DC), having a positive and negative pole and producing chemical changes when it
passes through the tissues and fluids of the body.
Opposite pole from the active electrode.
Invisible rays that have long wavelengths, penetrate the deepest, and produce the most heat.
Substance that does not easily transmit electricity.
147
iontophoresis (ionization)
jack
Process of introducing water-soluble products into the skin with the use of electric current such as the use of the
positive and negative poles of a galvanic machine.
Plug-in device used to make electrical contact.
kilowatt (K)
1,000 watts.
light therapy
The application of light rays to the skin for the treatment of disorders.
milliampere
milliampere meter
modalities
ohm (O)
plug
polarity
polarity changer
One-thousandth of an ampere.
Instrument that measures the rate of flow of an electric current.
Currents used in electrical facial and scalp treatments.
Unit that measures the resistance of an electric current.
Two- or three-prong connector at the end of an electrical cord that connects an apparatus to an electrical outlet.
Negative or positive pole of an electric current.
Switch that reverses with the direction of the current from positive to negative and vice versa.
rectifier
Apparatus that changes alternating current to direct current.
red light
Therapeutic light used on dry skin in combination with oils and creams; penetrates the deepest and produces the
most heat.
rheostat
Control that regulates the strength of the current used.
sinusoidal current
Alternating current similar to faradic current; produces mechanical contractions and is used during scalp and
facial manipulations.
Tesla high-frequency current Thermal or heat-producing current with a high rate of oscillation or vibration; also called violet ray.
therapeutic lamps
ultraviolet (UV) rays
visible light
volt (V)
Lamps used to produce artificial light rays in the salon.
Invisible rays that have short wavelengths, are the least penetrating rays, produce chemical effects, and kill
germs; also called cold rays or actinic rays.
Electromagnetic radiation that can be seen.
Unit that measures the pressure or force that pushes the flow of electrons forward through a conductor.
wall plate
Instrument that plugs into an ordinary wall outlet and produces different types of electric currents that are used
for facial and scalp treatments.
watt (W)
Measurement of how much electric energy is being used in one second.
wavelength
Distance between two successive peaks of electromagnetic waves.
white light
Referred to as combination light because it is a combination of all the visible rays of the spectrum.
Chapter 7
Basics of Electricity
7