spectrum

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spectrum

 [spek´trum] (L.)
1. the series of images resulting from the refraction of electromagnetic radiation (e.g., light, x-rays) and their arrangement according to frequency or wavelength.
2. range of activity, as of an antibiotic, or of manifestations, as of a disease. adj., adj spec´tral.
absorption spectrum one obtained by passing radiation with a continuous spectrum through a selectively absorbing medium.
broad-spectrum effective against a wide range of microorganisms.
visible spectrum that portion of the range of wavelengths of electromagnetic vibrations (from 770 to 390 nanometers) which is capable of stimulating specialized sense organs and is perceptible as light.

spec·trum

, pl.

spec·tra

,

spec·trums

(spek'trŭm, -ă, -ŭmz),
1. The range of colors presented when white light is resolved into its constituent colors by being passed through a prism or through a diffraction grating: red, orange, yellow, green, blue, indigo, and violet, arranged in increasing frequency of vibration or decreasing wavelength.
2. Figuratively, the range of pathogenic microorganisms against which an antibiotic or other antibacterial agent is active.
3. The plot of intensity versus wavelength of light emitted or absorbed by a substance, usually characteristic of the substance and used in qualitative and quantitative analysis.
4. The range of wavelengths presented when a beam of radiant energy is subjected to dispersion and focused.
[L. an image, fr. specio, to look at]

spectrum

/spec·trum/ (spek´trum) pl. spec´tra   [L.]
1. a charted band of wavelengths of electromagnetic radiation obtained by refraction or diffraction.
2. by extension, a measurable range of activity, as the range of bacteria affected by an antibiotic (antibacterial s.) or the complete range of manifestations of a disease.

absorption spectrum  that afforded by light which has passed through various gaseous media, each gas absorbing those rays of which its own spectrum is composed.
broad-spectrum  effective against a wide range of microorganisms; said of an antibiotic.
electromagnetic spectrum  the range of electromagnetic energy from cosmic rays to electric waves, including gamma, x- and ultraviolet rays, visible light, infrared waves, and radio waves.
fortification spectrum  a form of migraine aura characterized by scintillating or zigzag bands of colored light forming the edge of an area of teichopsia.
visible spectrum  that portion of the range of wavelengths of electromagnetic vibrations (from 770 to 390 nm) which is capable of stimulating specialized sense organs and is perceptible as light.

spectrum

(spĕk′trəm)
n. pl. spec·tra (-trə) or spec·trums
1. Physics
a. The entire range over which some measurable property of a physical system or phenomenon can vary, such as the frequency of sound, the wavelength of electromagnetic radiation, or the mass of specific kinds of particles.
b. A specific portion of such a range: the infrared spectrum.
c. A characteristic distribution of phenomena manifested over such a range: the emission spectrum for sodium vapor.
d. A graphic representation of such a distribution; a spectrogram.
e. A band of colors produced when the wavelengths making up white light are separated, as when light passes through a prism or strikes drops of water.
2.
a. A range of values of a quantity or set of related quantities: the income spectrum.
b. A sequence or range of related qualities, ideas, activities, entities, or phenomena: the whole spectrum of 20th-century thought; the spectrum of genes involved in the immune response.

spectrum

[spek′trəm] pl. spectra
Etymology: L, image
1 a range of phenomena or properties occurring in increasing or decreasing magnitude. Radiant or electromagnetic energy is arranged on the basis of wavelength and frequency. Electromagnetic radiation includes spectra of radio waves, infrared waves, visible light, ultraviolet waves, x-rays, and gamma rays. See also electromagnetic radiation, wave.
2 the range of effectiveness of an antibiotic. A broad-spectrum antibiotic is effective against a wide range of microorganisms. See also antibiotic.

spec·trum

, pl. spectrums, spectra (spek'trŭm, -trŭmz, -tră)
1. The range of colors presented when white light is resolved into its constituent colors by being passed through a prism or through a diffraction grating: red, orange, yellow, green, blue, indigo, and violet, arranged in increasing frequency of vibration or decreasing wavelength.
2. The range of pathogenic microorganisms against which an antibiotic or other antibacterial agent is active.
3. The plot of intensity versus wavelength of light emitted or absorbed by a substance, usually characteristic of the substance and used in qualitative and quantitative analysis.
4. The range of wavelengths presented when a beam of radiant energy is subjected to dispersion and focused.
[L. an image, fr. specio, to look at]

spectrum

colour image formed when white light passes through a prism; constituent colours (red, orange, yellow, green, blue, indigo, violet) are ranged in decreasing wavelength order, i.e. as a rainbow

spectrum

range of microorganisms against which an antibiotic is effective

spectrum 

1. Spatial display of a complex radiation produced by separation of its monochromatic components.
2. Composition of a complex radiation, e.g. continuous spectrum, line spectrum (CIE). Plural: spectra. See light.
absorption spectrum The curve representing the relative absorption of a pigment or chemical substance as a function of the wavelength of light. Example: the absorption spectrum of rhodopsin. Syn. absorbance spectrum.
action spectrum A graphical representation of the relative energy necessary to produce a constant biological effect. Example: frequency of action potentials in a ganglion cell as a function of wavelength.
continuous spectrum A spectrum in which, over a considerable range, all wavelengths exist without any abrupt variation in intensity. Example: the spectrum of hot solids. See filament lamp.
electromagnetic spectrum The total range of all electromagnetic waves. It extends from the longest radio waves of some thousands of metres in wavelength through radar, microwave, infrared rays, visible rays (between wavelengths 780nm and 380nm) to ultraviolet rays, X-rays, gamma rays and cosmic rays with wavelengths as short as 8 ✕ 10−12mm. All these electromagnetic waves differ only in frequency (and wavelength) but have the same speed as light in a vacuum.
equal energy spectrum Spectrum in which all wavelengths have about the same amount of energy. See achromatic; white light.
fortification spectrum See scintillating scotoma.
invisible spectrum The portions of the entire electromagnetic spectrum that are made up of radiations other than those of the visible spectrum.
line spectrum Spectrum consisting of a series of discrete monochromatic lines (or narrow bands of monochromatic light) with large intensity differences and separated by intervals without radiations. Example: the spectrum emitted by an electric discharge through a gas or vapour under low pressure.
spectrum locus The representation of the spectral colour stimuli on a chromaticity diagram.
solar spectrum The spectrum formed by sunlight. It is crossed at intervals by Fraunhofer's lines.
visible spectrum The portion of the electromagnetic spectrum that can be perceived by the visual system. It is composed of radiations of wavelengths in the range between 380nm and 780nm in younger eyes. This range decreases with age especially due to lens absorption of short wavelengths becoming closer to 420nm than 380nm. See light.

Table S4 Approximate values of the velocity, frequency and wavelength of electromagnetic radiations in a vacuum (the values represent a point within a range of radiations)
wavelength
radiationvelocity (m/s)frequency (Hz)(m)(nm)
AM radio3 ✕ 108 1 ✕ 106 3 ✕ 1023 ✕ 1011
television3 ✕ 108 1 ✕ 108 33 ✕ 109
radar3 ✕ 108 1 ✕ 109 3 ✕ 10−13 ✕ 108
microwave3 ✕ 108 1 ✕ 1010 3 ✕ 10−23 ✕ 107
thermal infrared3 ✕ 108 1 ✕ 1013 3 ✕ 10−53 ✕ 104
near infrared3 ✕ 108 1 ✕ 1014 3 ✕ 10−63000
light
red3 ✕ 1083.94 ✕ 10147.6 ✕ 10−7760
yellow3 ✕ 1085.45 ✕ 10145.5 ✕ 10−7550
violet3 ✕ 1087.50 ✕ 10144.0 ✕ 10−7400
ultraviolet3 ✕ 108 1 ✕ 1016 3 ✕ 10−830
X-rays3 ✕ 108 1 ✕ 1018 3 ✕ 10−100.3
gamma rays3 ✕ 108 1 ✕ 1021 3 ✕ 10−130.0003

spec·trum

, pl. spectrums, pl. spectra (spek'trŭm, -trŭmz, -tră)
1. Range of colors presented when white light is resolved into its constituent colors by being passed through a prism or through a diffraction grating: red, orange, yellow, green, blue, indigo, and violet.
2. Range of pathogenic microorganisms against which an antibiotic or other antibacterial agent is active.
[L. an image, fr. specio, to look at]

spectrum

pl. spectra, spectrums [L.]
1. the series of images resulting from the refraction of electromagnetic radiation (e.g. light, x-rays) and their arrangement according to frequency or wavelength.
2. range of activity, as of an antibiotic, or of manifestations, as of a disease.

absorption spectrum
one obtained by passing radiation with a continuous spectrum through a selectively absorbing medium.
antibacterial spectrum
the range of bacteria susceptible to a particular antimicrobial or class of antimicrobials.
broad-spectrum
effective against a wide range of microorganisms.
visible spectrum
that portion of the range of wavelengths of electromagnetic vibrations (from 770 to 390 nanometers) which is capable of stimulating specialized sense organs and is perceptible as light.

Patient discussion about spectrum

Q. What is the difference between autism, and autism spectrum? Doctor states my child is autistic, school says he has autism spectrum disorder. What is the difference? Can medication help with any of this?

A. i agree with Lilian- it's just a way for schools to keep their behinds clean...

Q. What is a "spectrum disorder" mean? I just heard/read about spectrum disorder, What is a "spectrum disorder" mean?

A. Autism is a spectrum disorder where symptoms and characteristics can present themselves in a wide variety of combinations, from mild to severe and in any combination. A high functioning individual with autism might simply seem eccentric, a loner. More severely affected individuals may hardly communicate and prefer to function primarily in "their own world". Most individuals fall in the middle of the spectrum.

Q. What shall I do with my 3 years old son with autism spectrum disorder. What shall I do with my 3 years old son with autism spectrum disorder to increase on his Sensory Integration. I feel therapy is too costly to afford….Is there any alternative.

A. there are some computer software that can do that too, and it doesn't cost all that much.they combine hearing- seeing and feeling.
i saw a computer USB contraption that also work int hat method and i think it costs 150-200 $ ...not sure....

More discussions about spectrum
References in periodicals archive ?
Table 4: Main frequency bands for UMTS/HSPA/LTE deployment - FDD mode 22
The 700 MHz band 26-- The 700 MHz band: a new harmonised frequency band for LTE?
LTE chipsets and devices 67 -- LTE FDD devices by frequency band -- TD-LTE devices by frequency band -- SoftBank TD-LTE smartphones -- China Mobile TD-LTE devices 15.
4GHz frequency band, has a range of about 100 meters and allows for connection speeds up to 11Mbps.
With RFID deployments expanding both globally and to a wider range of SKUs, a global tag that performs across all UHF frequency bands and is less sensitive to materials and orientation is clearly a benefit for our customers," says Bill Arnold, chief strategist at Omron RFID.
OmniGlobe's success has demonstrated that WiMAX is available today to support a service provider's requirements including multi-service infrastructure, a choice of frequency bands, reasonable cost, and ease of installation.
TechnoConcepts believes that True Software Radio(TM) is the only software-controlled frequency-agile transceiver semiconductor architecture that has been verified both in a lab environment and in public demonstrations and that can operate continuously across multiple frequency bands.
RFID applications in logistics are mostly within the 860-960 MHz, which stands in contradiction with the frequency band adopted in China telecom industry.
The AA1001's reprogrammable wideband transceiver overcomes all major challenges faced by WiMAX developers -- regional frequency band variation, multiple radio bandwidths and the need for low power.
It shows advantages and limitations of SDR at the present time, technology specifics, and stresses that SDR potentially allows to achieve a user dream: to build one universal device capable to support multiple national and international wireless standards in almost any frequency band.
Millimeter wave technology offering the performance of fiber for a fraction of the cost and installation time - the GigaLink(R) series of point-to-point radio systems, operating in the license-free frequency band of 60 GHz, offers throughput up to 1 Gbps with a range of enterprise and carrier network interfaces, and has proven to be a cost-effective solution for media companies, pharmaceutical manufacturers, medical centers, universities and other enterprises requiring bandwidth-intensive data transfers without the issues of installing fiber.

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