Photosensitivity is the amount to which an object reacts upon receiving photons of light. In quantum physics, the photon (from Greek φως, phōs, meaning light) is the quantum of the electromagnetic field (light). ... Prism splitting light Light is electromagnetic radiation with a wavelength that is visible to the eye (visible light) or, in a technical or scientific context, electromagnetic radiation of any wavelength. ...

Interpretation in medicine

People that are photosensitive experience discomfort or get easily sunburned when exposed to UV light, which may come from sunlight or other sources including sunbeds. This is often caused by an allergy or a medication. Note: Ultraviolet is also the name of a 1998 UK television miniseries about vampires. ... Prism splitting light Sunlight in the broad sense is the total spectrum of electromagnetic radiation given off by the Sun. ... A sunbed with lights off. ... An allergy can refer to several kinds of immune reactions including Type I hypersensitivity in which a persons body is hypersensitised and develops IgE type antibodies to typical proteins. ... Oral medication A medication is a licenced drug taken to cure or reduce symptoms of an illness or medical condition. ...

Interpretation in electronic engineering

Certain electronic devices, such as photodiodes and charge-coupled devices, are designed to be sensitive to light. They are constructed to take advantage of the photoelectric effect, the emission of electrons from matter upon the absorption of electromagnetic radiation. When light (one form of electromagnetic radiation) impinges on the active surface of such a device, electrical current flowing through or electrical charge stored in the device will increase or decrease in proportion to the intensity and wavelength of the light. This trait allows the device to perform regulating and sensing functions of many kinds. For example, a photoresistor circuit may sense ambient light to turn on a street lamp at dusk. Digital cameras use charge-coupled devices whose extreme sensitivity to light allows them to convert incoming photons into varying electrical charges with great accuracy. The varying charges are then encoded in a binary file which can be stored and later viewed on a computer screen or other medium. A photodiode is an electronic component and a type of photodetector. ... A specially developed CCD used for ultraviolet imaging in a wire bonded package. ... The photoelectric effect is the emission of electrons from matter upon the absorption of electromagnetic radiation, such as ultraviolet radiation or x-rays. ... Electromagnetic radiation can be conceptualized as a self propagating transverse oscillating wave of electric and magnetic fields. ... In electricity, current is the rate of flow of charges, usually through a metal wire or some other electrical conductor. ... Electric charge is a fundamental property of some subatomic particles, which determines their electromagnetic interactions. ... The wavelength is the distance between repeating units of a wave pattern. ... LDR A photoresistor is an electronic component whose resistance decreases with increasing incident light intensity. ... An electrical network is an interconnection of electrical elements such as resistors, inductors, capacitors, and switches. ... Digital cameras are a remarkable advance in technology. ... Computer files can be divided into two broad categories: binary and text. ...

Interpretation in chemistry

Chemicals that are photosensitive may undergo chemical reactions when exposed to light. These chemicals, such as hydrogen peroxide and many prescription drugs, are stored in tinted or opaque containers until they are needed to prevent photodegradation. Devices that are photosensitive include the human retina and photographic film. Film is photosensitive because its photosensitive material undergoes a chemical reaction when struck by light. A chemical reaction is a process that results in the interconversion of chemical substances [1]. The substance or substances initially involved in a chemical reaction are called reactants. ... Hydrogen peroxide (H2O2) is a clear liquid, slightly more viscous than water. ... Human eye cross-sectional view. ... Undeveloped Arista black and white film, ISO 125. ...

Typical substances that are photosensitive are alkali salts and silver halides. In chemistry, an alkali (from Arabic: al-qaly) is a specific type of base, formed as a carbonate, hydroxide or other ionic salt of an alkali metal or alkali earth metal element. ... For other meanings of the word salt see table salt or salt (disambiguation). ... A silver halide is one of the compounds formed between silver and one of the halogens, usually silver bromide (AgBr), silver chloride (AgCl) and silver iodide (AgI). ...

See also

• Heliotropism
• Photophobia
• Photosensitivity in animals

Phototropia is a botanical term for an organisms movement (tropism) in response to light. ... For the pathologic fear of light see the article on -phobia Photophobia (also light sensitivity) is a symptom of excessive sensitivity to light and the aversion to sunlight or well-lit places. ... Photosensitivity reactions, aka photosensitization, are abnormal skin reactions in animals when exposed to direct sunlight. ...

External links

• FDA article - Chemical Photosensitivity: Another Reason to Be Careful in the Sun