Light source, luminaire and surgical illumination unit
The Invention provides a light source, a luminaire and a surgical illumination unit in which two narrow-band light emitters both emit light in a narrow spectral peak having a full-width-half-maximum equal to or smaller than 40 nanometers. Both of the narrow-band light emitters have a different central emission wavelength within a blue color-range, within a green color range or within a red color-range. At least one of the two narrow-band light emitters comprises a luminescent material for generating the narrow spectral peak. The light source is further configured such that a distance between the narrow spectral peaks of the two narrow-band light emitters prevents overlap of the narrow spectral peaks. Due to the individual narrow spectral peaks, a color contrast within one of the color-ranges is significantly enhanced.
1. A light source, comprising:
a plurality of narrow-band light emitters, each emitting light in a narrow spectral peak having a full-width-half-maximum equal to or smaller than 40 nanometers and each narrow spectral peak having a central emission wavelength within a blue color-range or within a green color-range or within a red color-range;
at least one of the narrow-band light emitters comprising a luminescent material for generating the narrow spectral peak thereof; and
a distance between neighboring ones of the narrow spectral peaks of the narrow-band light emitters at half maximum intensity being configured to prevent overlap of the neighboring ones of the narrow spectral peaks,
wherein the neighboring ones of the narrow spectral peaks are directly adjacent and the distance is equal to or larger than 40 nanometers and configured to strengthen a contrast perceived between the directly adjacent spectral peaks, and
wherein a first central emission wavelength of the narrow spectral peaks within the red color-range corresponds to a color of a specific tissue to be operated upon by a surgical instrument, and a second central emission wavelength of the narrow spectral peaks corresponds to a color of the surgical instrument.
2. The light source according to claim 1 , wherein the first central emission wavelength lies within a wavelength range between 590 nanometers and 800 nanometers.
3. The light source according to claim 1 , wherein the luminescent material comprises any one of the materials from a list comprising: quantum dots, quantum rods or quantum tetrapods, nano-crystals, and rare earth metal complexes with narrow emission characteristics.
4. The light source according to claim 1 , wherein the blue color-range or green color-range or red color-range is expanded to an expanded wavelength range between 400 nanometers and 800 nanometers, and wherein the light source is configured to comprise five narrow-band light emitters each of the five narrow-band light emitters emitting light in a narrow spectral peak having a full-width-half-maximum equal to or smaller than 40 nanometers and each of the five narrow-band light emitters having a different central emission wavelength within the expanded wavelength range.
5. The light source according to claim 1 , wherein an overall light emission spectrum within the blue color-range, green color-range, red color-range, or within an expanded wavelength range further comprises light emitted in a wide spectral band having an intensity equal to or less than 25% of an average intensity of the narrow spectral peaks.
6. The light source according to claim 1 , wherein the luminescent material is arranged:
on a light exit surface of a light emitting device; and/or
in a vicinity of the light exit surface of the light emitting device; and/or
in a remote location from the light exit surface of the light emitting device.
7. The light source according to claim 1 , wherein at least one of the narrow-band light emitters is chosen from a list comprising: a Light Emitting Diode, an Organic Light Emitting Diode and a Laser Diode.
8. A luminaire comprising the light source of claim 1 .
9. A surgical light source comprising the light source of claim 1 .
10. The light source according to claim 3 , wherein the central emission wavelength of the narrow spectral peak of the light emitted by the at least one narrowband light emitter comprising the luminescent material is tuned to a predefined wavelength for enhancing a contrast of a predefined visible element.
11. The light source according to claim 4 , wherein a sum of the fullwidth-half-maximum value of the narrow spectral peaks within the expanded wavelength range is substantially equal to half the expanded wavelength range.
12. The light source according to claim 6 , wherein the luminescent material comprises a mixture of different luminescent materials, at least one of the different luminescent materials being a narrow-band light emitter emitting light at a different central wavelength and having a narrow spectral peak having a full-width-half-maximum equal to or smaller than 40 nanometers.
13. The light source according to claim 6 , wherein the light emission spectrum of the light source comprises light emitted by the light emitting device.