Terahertz explained

The band between radio and light.

Terahertz waves sit in a narrow slice of the electromagnetic spectrum that scientists only learned to work with in recent decades. Here's what it is, in plain words.

Find it on the map

PEMF explained

3 min read

On the spectrum

On the spectrum

Find terahertz on the map.

Every kind of electromagnetic wave lives on one spectrum, from slow radio waves to fast visible light. Hover or tap a band to see where it sits.

terahertz

OlyLife describes its terahertz band as 3–3000 µm

• radio
• terahertz
• visible

Radio, terahertz and light, side by side.

All three are the same kind of wave. What differs is how many times a second it repeats. Terahertz repeats far more often than radio and far less often than visible light.

Bar length shows the top of each band's frequency range, on a log scale.

A visual explainer of the technology's terms. It does not show any effect on the body.

• PEMF devices (typically 1–100 Hz) (1–100 Hz). PEMF devices typically pulse about 1 to 100 times per second. That is far slower than anything else on this ruler: it is a pulse rate, not a wave of radiation.
• Radio (about 10 kHz–1 GHz). Radio waves repeat from thousands to about a billion times per second. Broadcast and wireless signals use them.
• Microwave (about 1–100 GHz). Microwaves repeat billions of times per second. Radar, Wi-Fi and microwave ovens use them.
• Terahertz (0.1–10 THz) (0.1–10 THz). Terahertz sits between microwaves and infrared light. Scientists use it in security scanners and lab instruments.
• Infrared (about 10–400 THz). Infrared sits just above terahertz. TV remote controls and heat lamps use it.
• Visible light (about 400–790 THz). The narrow slice of the spectrum that our eyes can see.

The basics

The basics

A trillion waves a second.

What "tera" means

One terahertz (THz) is a trillion waves per second. The terahertz band usually means about 0.1 to 10 THz.

Between electronics and optics

It's too fast for ordinary radio electronics and too slow for most light-based tools. That's why engineers once called it the "terahertz gap".

How scientists use it

Today terahertz waves are used in security scanners, in quality checks for materials, and in lab instruments that identify substances by how they absorb the waves.

Water drinks it up

Water absorbs terahertz waves strongly. That's one reason they behave very differently from radio waves or visible light.

Wavelengths

Wavelengths

Two ways to measure a wave.

A wave can be described by how often it repeats (frequency) or by how long each wave is (wavelength). Slide to convert one into the other.

Wavelength

Frequency

Type a wavelength

{value} µm

≈ {value} THz

Terahertz band

Infrared band

A wave whose drawn length follows the slider

Frequency in THz is about 300 divided by the wavelength in µm. Drawn waves are not to scale.

OlyLife's band

In OlyLife devices

How OlyLife describes it.

• “OlyLife describes the Tera-P90 as combining bio-electromagnetic energy operating at 1 MHz with terahertz energy in a 3–3000 µm band.”^*
• “OlyLife calls terahertz the "light of life".”^*

— OlyLife's own descriptions

Terahertz appears in these OlyLife devices. Tap one to see how it's used.

• Tera-P90 — Terahertz
• Tera-P90+ — Terahertz
• Frost Age — Terahertz
• Vitality Wand — Terahertz

The range, in numbers

From infrared to terahertz.

Infrared

Terahertz

In physics terms, a 3 to 3000 µm range stretches from about 100 THz down to 0.1 THz. That covers the whole terahertz band and part of the infrared band next to it.

• 3 µm ≈ 100 THz
• 30 µm ≈ 10 THz
• 3000 µm ≈ 0.10 THz

Research

Research

A young field of science.

Terahertz research is mostly laboratory work on cells and tissues^†, exploring how these waves interact with living material.^‡

Browse the full research library

• Non-Thermal Effects of Terahertz Radiation on Gene Expression: Systematic Review and Meta-Analysis. Dione MN, et al. · Genes · 2024 · Meta-analysis · Very low evidence · Lab research only. Laboratory terahertz exposure produced gene-expression changes linked to stress and immune responses, but no consistent gene pattern could be identified. Read on PubMed
• Effect of terahertz radiation on cells and cellular structures. Rytik AP, et al. · Frontiers of Optoelectronics · 2025 · Review · Very low evidence · Lab research only. This narrative review summarizes laboratory findings on how terahertz radiation of varying power and duration affects cell viability, and discusses open safety questions. Read on PubMed

Questions

Questions

Good questions.

Is terahertz the same as infrared?

No, but they are neighbors. Terahertz is lower in frequency (about 0.1–10 THz); infrared starts just above it.

Is terahertz the same as PEMF?

No. PEMF is a magnetic field pulsing a few to a hundred or so times a second. Terahertz waves repeat about a trillion times a second. OlyLife's foot devices combine both. PEMF explained

Why does OlyLife call terahertz the "light of life"?

That's OlyLife's own name for it, from its product descriptions. It's a brand phrase, not a scientific term.

Does OlyLife publish a terahertz output figure?

Not at this time. OlyLife describes the band, but does not publish an output or intensity figure.

What does µm mean?

A micrometer: one millionth of a meter. A human hair is roughly 70 µm wide.