EP0119646A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Device for producing coherent radiation
Assignee: Koninklijke Philips NV
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Filing: 1984-02-20
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Granted: —
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Expires: 2004-02-20
Abstract
Abstract By means of electrons (7) of high energy produced by a semiconductor cathode (3), population inversion is obtained in an active layer (13) of a laser structure (11). In this manner, laser action is obtained, which offers advantages especially with II-VI materials which emit radiation of a wavelength shorter than the usual III-V materials, and which do not permit the desired population inversion to be obtained in the same manner as in III-V materials, by means of current injection across a pn junction. The semiconductor cathode (3) and the laser structure (2,11) can be both arranged in mutual separation in a vacuum tube (5) or be realized in one semiconductor body. The short-wave laser is especially advantageous for CD, DOR and VLP applications.
Inventors
- 👤 Joachim Hermann Wolter
- 👤 Robert Edward Horstman
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 09:37
CPC Classifications
H; H01; H01J; H01J1/00; H01J1/02; H01J1/30; H01J1/308; H01S; H01S3/00; H01S3/09; H01S3/0955; H01S3/0959
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
81 words
A device for producing or amplifying coherent electromagnetic radiation comprising at least a first body provided with at least a first layer of material suitable for producing or amplifying such radiation having at least an active region in which in the operating state population inversion is obtained by means of electron injection, characterized in that the device is provided with a semiconductor device comprising at least a semiconductor cathode for producing a beam of electrons for injection into the active region.
Claim 2
Independent Claim
81 words
A device for producing or amplifying coherent electromagnetic radiation comprising at least a first body provided with at least a first layer of material suitable for producing or amplifying such radiation having at least an active region in which in the operating state population inversion is obtained by means of electron injection, characterized in that the device is provided with a semiconductor device comprising at least a semiconductor cathode for producing a beam of electrons for injection into the active region.
Claim 3
Dependent Claim
22 words
A device as claimed in Claim 1, characterized in that the first layer comprises a mono-crystalline semiconductor body of a II-VI compcund.
Claim 4
Dependent Claim
43 words
A device as claimed in Claim 2, characterized in that the II-VI compound is formed from a compound of one or more of the elements zinc or cadmium with a compound of one or more of the elements oxygen, sulphur, selenium and tellurium.
Claim 5
Dependent Claim
23 words
A device as claimed in Claim 3, characterized in that the compound comprises doping to adjust the wavelength of the emitted electromagnetic radiation.
Claim 6
Independent Claim
20 words
A device as claimed in any one of Claims 1 to 4, characterized in that the active layer is strip-shaped.
Claim 7
Independent Claim
29 words
A device as claimed in any one of Claims 1 to 5, characterized in that the active layer is situated between two coating layers having a lower refractive index.
Claim 8
Independent Claim
160 words
A device as claimed in any one of Claims 1 to 6, characterized in that the semiconductor cathode comprises a semiconductor body with a pn junction between a p-type region and an n-type region which adjoins a surface of the semiconductor body, whereby, when a voltage is applied in the reverse direction across the pn junction in the semiconductor body, electrons are produced by avalanche multiplication, which electrons emanate from the semiconductor body, and the pn junction at least locally extends substantially parallel to the surface and has a lower breakdown voltage than the remaining part of the pn junction, the part having the lower breakdown voltage being separated from the surface by an n-type conducting layer having such a thickness and doping that at the breakdown voltage the depletion zone of the pn junction does not extend as far as the surface, but remains separated therefrom by a surface layer which is sufficiently thin to pass the electrons produced.
Claim 9
Dependent Claim
69 words
A device as claimed in Claim 7, characterized in that the surface of the semiconductor body is provided with an insulating layer in which at least one opening is provided, at least one acceleration electrode is provided on the insulating layer along the edge of the opening, and the pn junction extends at least within the opening substantially parallel to the surface and locally has a lower breakdown voltage.
Claim 10
Dependent Claim
22 words
A device as claimed in Claim 8, characterized in that the opening in the oxide has the form of a narrow gap.
Claim 11
Independent Claim
48 words
A device as claimed in any one of the preceding Claims, characterized in that the arrangement comprises a vacuum tube having in an evacuated envelope the first body and the semiconductor cathode, the first body being situated at the area of an end wall opposite the semiconductor cathode.
Claim 12
Independent Claim
27 words
A device as claimed in any one of Claims 1 to 9, characterized in that the first body is provided on the surface of the semiconductor cathode.
References Cited (Backward Citations)
US3393373A
Cited
US3655986A
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US3575627A
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US3715162A
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US3821773A
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GB2054959A
Cited
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