Table of contents

1. Principle description

2. Skin physical modeling

3. Skin heating mode

4. Security

5. Effectiveness

6. Parameter comparison

1. Principle description

The radio frequency current has penetrability, can pass through the epidermis to the dermis, and heats the dermis through the ohmic thermal effect. The temperature of the human dermis is relatively constant. Once the temperature rises, it will cause the collagen fibers to tighten and shrink, and at the same time stimulate the inflammatory cells to secrete FGF (a Peptide protein, which can enter the cell membrane), FGF promotes fibroblasts to produce collagen, elastin and hyaluronic acid (hyaluronic acid).

The ohmic heating effect refers to the calorific value Q=P∗T=U2Zc∗T, which is proportional to the square of the RF voltage (U) and the action time (T), and inversely proportional to the skin impedance (Zc). In common application scenarios of the ohmic heating effect, such as warm baby, there is a resistance impedance inside, and it will generate heat when the voltage is connected to the outside. Human skin is like a resistive impedance, and it will generate heat when a voltage is applied.

The principle of the home radio frequency beauty instruments is the same as that of medical beauty Thermage, both work through the ohmic heating effect of radio frequency current on the dermis.

The principle of radio frequency anti-aging

The premise of radio frequency anti-aging is that radio frequency energy can act on the dermis. Why radio frequency energy can act on the dermis requires us to physically model the skin.

2. Skin physical modeling

To solve skin problems with physical skin care, we need to physically model the skin. This is also the difference between this article and other articles about radio frequency beauty instruments. This article tries to analyze this matter from the principle:

The layering of the skin, the upper layer of the epidermis --- the bottom layer of the epidermis --- the papillary layer of the dermis --- the reticular layer of the dermis, each layer has the same structure and composition, and each layer is superimposed to form a capacitor. The pattern shown in the figure below can be drawn. Although the picture is ugly, the meaning is in place:

Physical model of the skin

For the convenience of analysis, we will equivalent the capacitance from the epidermis to the reticular layer of the dermis as three capacitances from top to bottom, and the three capacitances are connected in series:

1. The radio frequency beauty instrument penetrates the first capacitor and can act on the lower layer of the epidermis

2. The radio frequency beauty instrument penetrates the second capacitor and can act on the papilla layer of the dermis

3. The RF beauty instrument penetrates the third capacitor and can act on the reticular layer of the dermis

Similar to skin care products, penetration ability is still the most difficult task of physical skin care. It is more difficult for radio frequency energy to penetrate downwards. Penetrating the third capacitor to act on the reticular layer of the dermis is the result we need.

We borrow a physical formula to understand the resistance to this penetration, which is the capacitive reactance of the skin:

Zc=1jwc

c is the capacitance of the skin, j is the unit of the frequency domain, w=2 π f, and f is the frequency of the RF beauty instrument, obviously, f is inversely proportional to the capacitive reactance of the skin (the resistance encountered by penetration). As shown below:

Schematic diagram of frequency and depth of action

In the picture above, 1Mhz is the most RF beauty device, 4.2Mhz is the DLUS RF beauty device, and 6.78Mhz is the fifth generation Thermage. Because the other "negative plate" of Thermage is relatively far away, the RF current of Thermage seems to diverge.

The second golden sentence: The current penetration depth of the radio frequency beauty instrument is determined by the frequency, and the resistance encountered in penetration is inversely proportional to the frequency. The higher the frequency, the smaller the resistance, that is, the higher the frequency, the deeper the penetration depth.

3. Skin heating mode

As mentioned earlier, the premise of radio frequency anti-aging is that radio frequency energy acts on the dermis, so the penetration depth determines whether radio frequency skin care is effective. According to the different penetration depths, there are currently two working modes for home radio frequency beauty instruments:

·Volume heating: The frequency of the radio frequency instrument is greater than 4Mhz, acting on the entire dermis reticular layer, heating from the inside out, the heat is mild and long-lasting, but still needs to add protection measures to prevent scalding the skin.

·Area heating: The frequency of the radio frequency instrument is 1~2Mhz. It acts on the epidermis and directly heats the epidermis. The heat is intense and easy to burn. Protective measures must be added to prevent scalding the skin. Displacement sensors, temperature sensors, and current detection methods can be used for protection.

4. Security

The mechanism of radio frequency skin care is safe: it is a beauty method that applies external stimuli to activate the body's own potential, not implant care, and will not trigger chemical reactions.

·Temperature protection of radio frequency instruments: There is a natural game between the effectiveness and safety of radio frequency instruments. The effect is obvious when the temperature is high, but the risk of burns also rises sharply. To solve this contradiction, we need to jump out of the circle of the game and solve it in a higher dimension -----increase the frequency, let the radio frequency current act on the deeper dermal reticular layer, and realize volume heating, not only for the area heating of the epidermis- ----Improve the effect and greatly reduce the risk of burns.

The third golden sentence: The radio frequency beauty instrument can realize the heating of the dermis instead of the burning of the epidermis. The frequency must be sufficient so that the energy can act on the reticular layer of the dermis. At this time, the safety of the radio frequency instrument is also guaranteed. Without frequency, there is nothing.

5. Effectiveness

First of all, ensure that the RF beauty instrument can act on the reticular layer of the dermis. At this time, the ohmic heating effect of the radio frequency current will stimulate the inflammatory cells in the reticular layer of the dermis to secrete FGF, and FGF will promote the fibroblasts to produce new collagen.

First of all, ensure that the RF beauty instrument can act on the reticular layer of the dermis. At this time, the ohmic heating effect of the radio frequency current will stimulate the inflammatory cells in the reticular layer of the dermis to secrete FGF, and FGF will promote the fibroblasts to produce new collagen.

6. Parameter comparison

Seeing this, we have some understanding of the principles of radio frequency skin care and anti-aging. Let's take a look at the comparison of several representative radio frequency beauty instruments:

Comparison of RF Beauty Instrument Parameters

Strictly speaking, Dr.Arrivo is not a radio frequency instrument, but considering that many users are paying attention to Dr.Arrivo, Dr.Arrivo is also included here.

The fourth golden sentence: RF current is a definite physical quantity that can be measured 100%. The effect of RF current on skin care has a solid theoretical basis and strong practical proof. When purchasing a radio frequency beauty instrument, we should not only focus on the efficacy report of a certain product or brand (there are commercial operations or unscientific sample size), the most important thing for us is to directly compare the key parameters (radio frequency) to make a basic judgment.

The radio frequency beauty instrument activates skin activity through heat, just like the more exercise the body becomes, the healthier it is, and the human body's functions are unlimited.