Light-emitting device and optical intergrated device

Abstract

In fabricating a monochromic and highly coherent light source, no single crystalline bulk semiconductor is used, but two different kinds of transparent substances are alternately stacked over each other to constitute a periodic structure in ½ of the intended wavelength. At least one of the two kinds of transparent substances is controllable in electric conductivity, and the structure is such that inside a medium consisting of this kind of transparent substance light-emitting semiconductor particulates are embedded. Accordingly, a light-emitting device has this structure, which makes possible control of the center wavelength of light emission, the width of wavelength distribution and coherence by adjusting the geometrical parameters of the device without having to alter the kind of material use.

What is claimed is:  
     
         1 . A light-emitting device having a characteristic of light emission by electrical excitation, and a periodic structure in which first dielectrics transparent in the light-emitting wavelength range of the characteristic of said light emission and second dielectrics having a different dielectric constant from said first dielectrics are alternately combined.  
     
     
         2 . The light-emitting device, as claimed in  claim 1 , wherein the first dielectrics and the second dielectrics are combined in units of ½ periods of the wavelength of light emission from the first dielectrics.  
     
     
         3 . The light-emitting device, as claimed in  claim 1 , wherein the light-emitting first dielectrics have a structure in which light-emitting semiconductor particulates are uniformly dispersed in these dielectric media.  
     
     
         4 . The light-emitting device, as claimed in  claim 1 , wherein the light-emitting first dielectrics have a structure in which light-emitting semiconductor particulates are uniformly dispersed in transparent media; said transparent media are electroconductive; and their electrical conductivity is lower than that of said semiconductor particulates.  
     
     
         5 . An optical integrated device, in which a light-emitting device has a periodic structure where first dielectrics emit light when excited by electrical excitation and are transparent in the light-emitting wavelength range of said light emission characteristic and second dielectrics having a different dielectric constant from said first dielectrics are alternately combined, said light-emitting device serves as a light source having a narrow width of wavelength distribution and high coherence, and is integrally formed with such optical components as a light detecting device, microlenses for collimating and condensation, and a hologram device.  
     
     
         6 . The optical integrated device, as claimed in  claim 5 , wherein the first dielectrics and the second dielectrics are combined in units of ½ periods of the wavelength of light emission from the first dielectrics.  
     
     
         7 . The optical integrated device, as claimed in  claim 5 , wherein the light-emitting first dielectrics have a structure in which light-emitting semiconductor particulates are uniformly dispersed in these dielectric media.  
     
     
         8 . The optical integrated device, as claimed in  claim 5 , wherein the light-emitting first dielectrics have a structure in which light-emitting semiconductor particulates are uniformly dispersed in transparent media; said transparent media are electroconductive; and their electrical conductivity is lower than that of said semiconductor particulates.  
     
     
         9 . An optical integrated device, in which a light-emitting device has a periodic structure where first dielectrics emit light when excited by electrical excitation and are transparent in the light-emitting wavelength range of said light emission characteristic and second dielectrics having a different dielectric constant from said first dielectrics are alternately combined, wherein said light-emitting device serves as a light source having a narrow width of wavelength distribution and high coherence, and is integrally formed with such optical components as a light detecting device, microlenses for collimating and condensation, and a hologram device, and wherein said optical integrated device having an optical pickup function.  
     
     
         10 . The optical integrated device, as claimed in  claim 9 , wherein the first dielectrics and the second dielectrics are combined in units of ½ periods of the wavelength of light emission from the first dielectrics.  
     
     
         11 . The optical integrated device, as claimed in  claim 9 , wherein the light-emitting first dielectrics have a structure in which light-emitting semiconductor particulates are uniformly dispersed in these dielectric media.  
     
     
         12 . The optical integrated device, as claimed in  claim 9 , wherein the light-emitting first dielectrics have a structure in which light-emitting semiconductor particulates are uniformly dispersed in transparent media; said transparent media are electroconductive; and their electrical conductivity is lower than that of said semiconductor particulates.  
     
     
         13 . An optical integrated device having a configuration wherein a probe light from a first light source comes incident obliquely at a prescribed angle to an axis perpendicular to an object surface and reaches an irradiation point, a second light source of the same specification as said first light source is arranged in a position axially symmetrical to said perpendicular axis, and a probe light from said second light source, similar to the probe light from the first light source, reaches said irradiation point, said optical integrated device having an optical pickup function.  
     
     
         14 . The optical integrated device, as claimed in  claim 13 , wherein the irradiation point is defined on the object surface; two probe light irradiating lines symmetrical with respect to a perpendicular line starting from this irradiation point are provided; and said two probe light lines come incident on the irradiation point at an angle of 40 degrees or more to each other.  
     
     
         15 . An optical integrated device having a configuration wherein an irradiation point is defined on an object surface; two probe light irradiating lines symmetrical with respect to a perpendicular line starting from this irradiation point are provided; and said two probe light lines reach and come incident on the irradiation point at a prescribed angle to each other; lights resulting from the reflection, scattering and diffraction of said probe lights from the object surface being condensed and re-introduced into light sources belonging to said probe light irradiating lines to be fed back to and detected in an active region.  
     
     
         16 . An optical integrated device comprising: a first probe light irradiating line so configured that a probe light from a first light source is introduced into an optical waveguide and transmitted, comes incident via an objective lens obliquely at a prescribed angle to a perpendicular axis to an object surface and reaches an irradiation point; and a second probe light irradiating optical line having the same configuration as this first probe light irradiating line, wherein these first probe light irradiating line and second probe light irradiating optical line are arranged in symmetric positions with respect to said perpendicular axis.  
     
     
         17 . An optical integrated device comprising: a first probe light irradiating line so configured that a probe light from a first light source is introduced into an optical waveguide and transmitted, comes incident via an objective lens obliquely at a prescribed angle to a perpendicular axis to an object surface and reaches an irradiation point; and a second probe light irradiating optical line having the same configuration as this first probe light irradiating line, and the optical integrated device having a configuration in which: these first probe light irradiating line and second probe light irradiating optical line are arranged in symmetric positions with respect to said perpendicular axis; and the two probe lights reach said irradiating point, wherein lights resulting from the reflection, scattering and diffraction of said probe lights from the object surface are condensed and re-introduced into light sources belonging to said probe light irradiating lines to be fed back to and detected in an active region.  
     
     
         18 . The optical integrated device, as claimed in  claim 15 , having an optical pickup function.  
     
     
         19 . The optical integrated device, as claimed in  claim 16 , having an optical pickup function.  
     
     
         20 . The optical integrated device, as claimed in  claim 17 , having an optical pickup function.