Surface-emission laser array, optical scanning apparatus and image forming apparatus

• US 8,508,567 B2
• Filed: 11/28/2011
• Issued: 08/13/2013
• Est. Priority Date: 04/28/2006
• Status: Active Grant

• Current Assignee: Ricoh Company Limited
• Original Assignee: Ricoh Company Limited
• Inventors: Sato, Shunichi, Itoh, Akihiro, Shouji, Hiroyoshi, Hayashi, Yoshinori, Ichii, Daisuke, Hara, Kei, Fujii, Mitsumi
• Primary Examiner(s): PHAM, HAI CHI
• Application Number:
  US13/304,874
• Publication Number:
  US 20120069416A1
• Time in Patent Office: 624 Days
• Field of Search: 347/233, 347/238
• US Class Current: 347/238
• CPC Class Codes: B41J 2/45 using light-emitting diode [LED] or laser arrays
• CPC Class Codes: B41J 2/473 using multiple light beams, wavelengths or colours
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: G02B 26/123 Multibeam scanners, e.g. using multiple light sources or beam splitters
• CPC Class Codes: H01S 5/18311 using selective oxidation
• CPC Class Codes: H01S 5/18358 containing spacer layers to adjust the phase of the light wave in the cavity
• CPC Class Codes: H01S 5/3432 the whole junction comprising only (AI)GaAs
• CPC Class Codes: H01S 5/423 having a vertical cavity

Abstract

A surface-emission laser array comprises a plurality of surface-emission laser diode elements arranged in the form of a two-dimensional array including a plurality of columns of the surface-emission laser diode elements, each column including therein at least two surface-emission laser diode elements in a first direction. The surface-emission laser diode elements in a column are disposed with an equal interval in the first direction. The plural columns arc disposed in a second direction which is perpendicular to the first direction. An interval between two adjacent columns is larger in a central part than in a peripheral part of the two-dimensional array of the surface-emission laser diode elements in the second direction.

Claims

1. A surface-emission laser array comprising a plurality of surface-emission laser diode elements forming a two-dimensional array,

wherein there are provided a plurality of columns of said surface-emission laser diode elements including therein at least two surface-emission laser diode elements in a first direction, such that said column of surface-emission laser diode elements is disposed in plural number in a second direction perpendicular to said first direction,

said plurality of the surface-emission laser diode elements are disposed with an equal interval in said first direction,

said plurality of surface-emission laser diode elements are disposed such that an interval between two adjacent columns of said surface-emission laser diode elements is larger in a central part than in a peripheral part of said two-dimensional array of said surface-emission laser diode elements in said second direction,

a number of said columns being larger than a number of said surface-emission laser diode elements included in one column.

2. The surface-emission laser array as claimed in claim 1, wherein said interval of said surface-emission laser diode elements in said column as measured in said first direction is et smaller than a maximum of said interval of said plurality of surface-emission laser diode elements as measured in said second direction.

3. The surface-emission laser array as claimed in claim 1, wherein said plurality of columns comprises a first column and a second column, and wherein a number of said surface-emission laser diode elements constituting said first column is different from a number of said surface-emission laser diode elements constituting said second column.

4. The surface-emission laser array as claimed in claim 1, wherein, in two adjacent columns of said plurality of columns, the interval between two nearest surface-emission laser diode elements as measured in said first direction is different from the interval of said plurality of surface-emission laser diode elements as measured in said first direction.