OPTICAL BEAM GENERATING DEVICE

• US 20100060969A1
• Filed: 09/14/2007
• Published: 03/11/2010
• Est. Priority Date: 11/28/2006
• Status: Active Grant

• Current Assignee: Hamamatsu Photonics KK
• Original Assignee: Hamamatsu Photonics KK
• Inventors: Ando, Taro, Ohtake, Yoshiyuki, Ito, Haruyasu, Matsumoto, Naoya, Fukuchi, Norihiro
• Granted Patent: US 7,961,371 B2
• Time in Patent Office: Days
• US Class Current: 359/238
• CPC Class Codes: G02B 21/32 Micromanipulators structurally combined with microscopes
• CPC Class Codes: G02B 26/06 for controlling the phase of light G02B26/08 takes precedence , measuring optical phase difference G01J9/00
• CPC Class Codes: G02B 27/09 Beam shaping, e.g. changing the cross-sectional area, not otherwise provided for adapting the beam shape of a laser diode G02B19/0052; adapting the beam shape of an LED G02B19/0061; coupling into light guides using intermediate optical elements G02B6/4204; beam shaping specially adapted for lasers H01S3/005
• CPC Class Codes: G02B 5/3025 Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state G02B5/3008, G02B5/3016 take precedence

Abstract

The light beam generator 1 is provided with a laser light source 10, an optical phase modulation element 15 and others. The optical phase modulation element 15 receives coherent light output from the laser light source 10 and passed through a beam splitter 14 to modulate a phase of the light depending on a position on the beam cross section of the light, and outputs the light after the phase modulation to the beam splitter 14. A polar coordinate system (r, θ) in which a predetermined position is given as an origin is set on the beam cross section of the light input in the optical phase modulation element 15, and when (p+1) domains divided by p (number of pieces) circumferences in which the predetermined position is given as a center are set, of these (p+1) domains, a phase modulation amount φ at each position inside an even numbered domain counted from the inside is expressed by a formula of “φ=q θ”, and a phase modulation amount φ at each position inside an odd numbered domain counted from the inside is expressed by a formula of “φ=q θ+π”.

Claims

1. A light beam generator including:

a light source of outputting coherent light; and

an optical phase modulation element which receives the light output from the light source to modulate a phase of the light depending on a position on a beam cross section of the light, and outputs the light after the phase modulation;

wherein

a polar coordinate system (r, θ

) having an origin at a predetermined position is set on the beam cross section of the light input in the optical phase modulation element, and when (p+1) domains divided by p (number of pieces) circumferences in which the predetermined position is given as a center are set, of these (p+1) domains, a phase modulation amount φ

at each position inside an even-numbered domain counted from the inside is expressed by a formula of “

φ

=q θ

” and

a phase modulation amount φ

at each position inside an odd-numbered domain counted from the inside is expressed by a formula of “

φ

=q θ

+π

”

, however, provided that p is a natural number and q is an integer other than zero.

2. The light beam generator according to claim 1, wherein the optical phase modulation element is an element in which a phase modulation amount of each pixel is set on the basis of a control signal input from outside.