Light-emitting device and a display apparatus having a light-emitting device

• US 6,586,775 B2
• Filed: 03/20/2000
• Issued: 07/01/2003
• Est. Priority Date: 03/19/1999
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Hirayama, Yuzo
• Primary Examiner(s): Flynn, Nathan J.
• Assistant Examiner(s): Mondt, Johannes P
• Application Number:
  US09/531,490
• Publication Number:
  US 20030071564A1
• Time in Patent Office: 1,198 Days
• Field of Search: 257/13, 257/79, 257/82, 257/86, 257/918, 257/98, 313/522, 313/112-3, 313/461, 313/464, 392/376
• US Class Current: 257/98
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: G02B 6/1225 comprising photonic band-gap structures or photonic lattices
• CPC Class Codes: H01J 63/04 Vessels provided with luminescent coatings; Selection of materials for the coatings
• CPC Class Codes: H01K 1/08 Metallic bodies
• CPC Class Codes: H01K 1/10 Bodies of metal or carbon combined with other substance
• CPC Class Codes: H01K 1/14 characterised by the shape
• CPC Class Codes: H01K 1/28 Envelopes; Vessels

Abstract

A light emitting device which emits visible light through heat radiation of a tungsten filament. Photonic crystal structures in each of which Ag spheres are arranged in a TiO₂ film are provided around the filament. Whereas radiation of infrared light from the filament is suppressed, radiation of visible light is enhanced.

Claims

1. A light-emitting device, comprising:

a first filament configured to radiate first light having an intensity peak at a first wavelength by allowing a current to flow in said first filament; and

a photonic crystal structure provided surrounding said first filament, said photonic crystal structure receiving said first light from said first filament and suppressing radiation of said first light to increase an intensity of second light having an intensity peak within the visible light wavelength region, said second light radiated from said photonic crystal structure as visible light,

wherein said first filament is provided with first holes, said first holes arranged periodically along a direction in which said first filament extends.

2. A light-emitting device according to claim 1, wherein said first filament crosses a second filament provided with second holes, said second holes arranged periodically along a direction in which said second filament extends.

3. A light-emitting device, comprising:

a first filament configured to radiate first light having an intensity peak at a first wavelength by allowing a current to flow in said first filament; and

a photonic crystal structure provided surrounding said first filament, said photonic crystal structure receiving said first light from said first filament and suppressing radiation of said first light to increase an intensity of second light having an intensity peak within the visible light wavelength region, said second light radiated from said photonic crystal structure as visible light,

wherein said photonic crystal structure comprises a first photonic crystal body having a trench and a second photonic crystal body, said first and second photonic crystal bodies combined with each other with said trench interposed therebetween such that said first filament passes through said trench.