Wavelength converter; and light emitting device, medical system, electronic apparatus, and inspection method using same
View Patent ↗A wavelength converter includes a first phosphor activated with Cr 3+ ; and a second phosphor activated with at least one ion of Ce 3+ or Eu 2+ . A fluorescence spectrum of a fluorescence emitted by the second phosphor has a peak where a fluorescence intensity shows a maximum value in a wavelength range of 500 nm or more to less than 580 nm. The wavelength converter emits a fluorescence having a light component over an entire range of 500 nm or more to less than 580 nm. The wavelength converter emits a light having a spectrum in which a ratio of a minimum light emission intensity to a maximum light emission intensity is 40% or less in a wavelength range of 550 nm or more to 700 nm or less.
1. A wavelength converter, comprising:
a first phosphor activated with Cr 3+ ; and
a second phosphor activated with at least one ion of Ce 3+ or Eu 2+ , wherein
a fluorescence spectrum of a fluorescence emitted by the second phosphor has a peak where a fluorescence intensity shows a maximum value in a wavelength range of 500 nm or more to less than 580 nm,
the wavelength converter emits a fluorescence having a light component over an entire range of 500 nm or more to less than 580 nm, and
the wavelength converter emits a light having a spectrum in which a ratio of a minimum light emission intensity to a maximum light emission intensity is 40% or less in a wavelength range of 550 nm or more to 700 nm or less,
wherein a wavelength having the maximum light emission intensity is 550 nm or more and less than 580 nm, and a wavelength having the minimum light emission intensity is 580 nm or more and 700 nm or less.
2. The wavelength converter according to claim 1 , wherein a fluorescence spectrum of a fluorescence emitted by the first phosphor has a peak where a fluorescence intensity shows a maximum value in a wavelength range of 710 nm or more.
3. The wavelength converter according to claim 1 wherein the second phosphor is activated with Ce 3+ .
4. A light emitting device, comprising:
the wavelength converter according to claim 1 ; and
a light source configured to emit a light that is wavelength-converted by the wavelength converter.
5. The light emitting device according to claim 4 , wherein the light emitted by the light source is a laser light.
6. The light emitting device according to claim 5 , wherein a spectrum of the light emitted by the light source has a peak where a intensity shows a maximum value in a wavelength range of 420 nm or more to less than 480 nm, and
the light emitted by the light source is a blue light.
7. The light emitting device according to claim 6 , wherein the light source includes a solid-state light emitting device, and
the blue light is emitted by the solid-state light emitting device.
8. The light emitting device according to claim 4 , wherein the light emitting device is a light source for a sensing system, or an illumination system for a sensing system.
9. A medical system, comprising:
the light emitting device according to claim 4 .
10. The medical system according to claim 9 , wherein the medical system is used in either a fluorescence imaging method or a photodynamic therapy.
11. The medical system according to claim 9 , further comprising:
a first image sensor configured to detect reflected light of a visible light component emitted by the light emitting device; and
a second image sensor configured to detect a fluorescent component of near infrared light emitted by a drug, wherein
the drug is excited by a light emitted by the light emitting device.
12. An electronic apparatus, comprising:
the light emitting device according to claim 4 .
13. The electronic apparatus according to claim 12 , wherein the electronic apparatus is any one of an information recognition device, a sorting device, a detection device, or an inspection device.
14. The electronic apparatus according to claim 13 , wherein the inspection device is any one of a medical inspection device, an agricultural and livestock inspection device, a fishery inspection device, or an industrial inspection device.
15. An inspection method, comprising:
using the light emitting device according to claim 4 .
16. The light emitting device according to claim 4 , wherein the light emitted by the light source is a continuous pulsed light.
17. An endoscope, comprising:
the light emitting device according to claim 4 .