How to Choose a Near Infrared Bulb

The marketplace offers a wide range of red light and infrared products for home use by consumers. These include incandescent bulbs of varying sizes and wattages; walk in infrared saunas; and LED infrared bulbs, panels, face masks, and helmets. Prices range from less than $30 to more than $5000. While this variety presents the opportunity to find a product that is the perfect fit, the choices can be overwhelming without a means of comparing products in a meaningful way. Fortunately, there are some objective criteria that you can use to find the product that will be best for you.

What are Red Light and Infrared Energy?

Red light and infrared energy are parts of the electromagnetic spectrum. This is a band of energy, in which, types of energy are classified by wavelength. Among the types of energy in the electromagnetic spectrum is light. This includes light that can be seen by the naked eye and light that cannot.

Both red light and near infrared energy are types of light, although infrared energy is not perceptible without special equipment. Red light is energy that has wavelengths between 650 nanometers (nm) and 699 nm. Infrared energy has wavelengths between 700nm and 3000nm. Near infrared is a subset of infrared energy, having wavelengths between700nm and 1000nm.

There is a fair bit of confusion about the difference between near infrared and infrared energy, mainly because the terms are often used interchangeably, as we do throughout this article. The difference between the two is the wavelengths of the energy, as described above. All near infrared energy is infrared energy.

Do All Red Light and Near Infrared Products Produce Heat?

Not necessarily. Whether a product generates heat or not is dependent upon the type of technology. All incandescent bulbs produce heat, meaning all are heat lamp bulbs. For example, TheraBulb’s incandescent line offers operating temperatures from 518°F to 589°F, depending upon the wattage of the bulb. Most infrared saunas produce heat as well, unless they are an LED sauna. LED products do not produce heat. Therefore, if you are looking for a product that produces heat as well as red light and near infrared energy, you’ll want to choose something other than an LED bulb.

Do All Red Light and Near Infrared Products Put Out the Same Amount of Energy?

Red light bulbs and other (near) infrared products vary in intensity. The technical term for intensity of light is irradiance, and it is measured in milliwatts per centimeter squared(mW/cm2). Irradiance is similar to the brightness of visible light in that it decreases as distance from the source increases. (Think of how a lightbulb seems much brighter when you are beside it than when you are across the room from it.) For this reason, irradiance data always includes the distance from the source, such as .33M, .5M, 1M. Larger irradiance numbers at a given distance indicate more energy available at that distance.

What About EMF?

Electromagnetic fields (EMF) are produced by some electrical devices and some people have a sensitivity to them. Fortunately, one category of red light and infrared products is EMF-free by design. The way that incandescent light bulbs operate—namely, by passing current through a metal filament to make it glow and become hot—does not produce EMF. This is a fact known by scientists and which TheraBulb has had verified through independent laboratory testing of our bulbs. If EMF is a concern for you and you are considering a non-incandescent product, such as LED, ask the manufacturer for the amount of EMF emitted by the product.

Note: Electromagnetic fields should not be confused with the electromagnetic spectrum, which is a band of naturally occurring energy, such as light.

How Do I Compare Products?

Setting aside product form, which is truly an individual choice, a meaningful basis for comparison is how the products perform. To make a functional comparison, you’ll want to gather some data on each product. Here are the attributes to evaluate:

• Temperature: Do you want a product that produces heat? If so, how hot would you like it to get?
• Wavelengths: Does the product emit energy between 650nm and 1000nm?
• Spectral Distribution: How much of the total energy output of the bulb is red light? How much is near infrared?
• Peak Wavelength: Of the energy emitted by the product, what is the wavelength of the largest percentage (referred to as “peak wavelength”)? Is the peak wavelength between 650nm and 1000nm?
• Irradiance: How concentrated is the energy emitted by the product at a given distance?
• EMF: If you are EMF sensitive, you’ll want to know whether or not the product puts out EMF and how much?

How Do I Get Data to Make a Comparison?

Most companies have some or all of this data on their websites or in their product literature. If any is not among the information available online, feel free to ask the manufacturer.

In addition to gathering the data itself, you’ll want to find out how the data was collected. Specifically, you’ll want to know if the product was tested in an independent laboratory. This is especially important with regard to irradiance. Some manufacturers measure irradiance in the factory using a tape measure and light meter rather than subjecting the product to a laboratory test. Measuring irradiance this way creates a result that is inflated and unreliable for several reasons, including the fact that ambient light has not been filtered out in the tape measure/light meter test method. Accuracy and transparency are the reasons that TheraBulb has invested in having our bulbs tested in one of the same ISO 17025 accredited laboratories that tests electrical products for the US Department of Defense.