Head-mounted microscope reaches deeper into mouse brains

Researchers have developed a miniature microscope that is designed for high-resolution 3D images inside the brains of living mice. By imaging deeper into the brain than previously possible with miniature widefield microscopes, ...

Diseases, Conditions, Syndromes

Ultraviolet light has bright future in fight against COVID-19

A particular type of ultraviolet light known as far-UVC could be safely used for air disinfection in public places without harming people, according to new research carried out jointly at the University of St Andrews and ...

Radiology & Imaging

Exploring the deep tissues using photoacoustic imaging

Photoacoustic imaging has gained global attention for capturing images without causing pain or using ionizing radiation. Recently, many researchers have heavily studied observing deep tissues to apply photoacoustic imaging ...


Lasting symptom relief with class IV laser in epicondylitis

(HealthDay)—Treatment with a dual wavelength 10 W class IV laser correlates with long-term relief of the symptoms associated with chronic epicondylitis, according to a study published in the July issue of Lasers in Surgery ...


New technology shows diabetes

A new imaging method for the study of insulin-producing cells in diabetes among other uses is now being presented by a group of researchers at Umeå University in Sweden in the form of a video in the biomedical video journal, ...

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In physics, the wavelength of a sinusoidal wave is the spatial period of the wave – the distance over which the wave's shape repeats. It is usually determined by considering the distance between consecutive corresponding points of the same phase, such as crests, troughs, or zero crossings, and is a characteristic of both traveling waves and standing waves. Wavelength is commonly designated by the Greek letter lambda (λ). The concept can also be applied to periodic waves of non-sinusoidal shape. The term wavelength is also sometimes applied to modulated waves, and to the sinusoidal envelopes of modulated waves or waves formed by interference of several sinusoids.

Assuming a sinusoidal wave moving at a fixed wave speed, wavelength is inversely proportional to frequency: waves with higher frequencies have shorter wavelengths, and lower frequencies have longer wavelengths.

Examples of wave-like phenomena are sound waves, light, and water waves. A sound wave is a periodic variation in air pressure, while in light and other electromagnetic radiation the strength of the electric and the magnetic field vary. Water waves are periodic variations in the height of a body of water. In a crystal lattice vibration, atomic positions vary periodically in both lattice position and time.

Wavelength is a measure of the distance between repetitions of a shape feature such as peaks, valleys, or zero-crossings, not a measure of how far any given particle moves. For example, in waves over deep water a particle in the water moves in a circle of the same diameter as the wave height, unrelated to wavelength.

This text uses material from Wikipedia, licensed under CC BY-SA