scispace - formally typeset
Search or ask a question
Topic

Optical modulator

About: Optical modulator is a research topic. Over the lifetime, 14068 publications have been published within this topic receiving 196932 citations.


Papers
More filters
Patent
Kouichirou Shinohara1
24 Nov 1992
TL;DR: In this paper, a laser scanner is described, in which the lateral magnification obtained from the first and second optical members, the scanning velocity of the scanning beam on the beam receiving surface and the velocity of acoustic wave inside the acoustic beam modulator are substantially related by M −V 1 /V s, comprising a laser beam emitter, an acoustic optical modulator which generates an acoustic wave having a specified direction of progression, a first optical member to make the primary diffracted beam a collimated beam, a beam deflecting means to deflect the collimated beacon to make it a scanning
Abstract: A laser scanner is disclosed, in which M, the lateral magnification obtained from the first and the second optical members, V 1 , the scanning velocity of the scanning beam on the beam receiving surface and V s , the velocity of the acoustic wave inside the acoustic beam modulator are substantially related by M=-V 1 /V s , comprising a laser beam emitter, an acoustic optical modulator which generates an acoustic wave having a specified direction of progression to modulate a laser beam emitted from the laser beam emitter and obtain a primary diffracted beam, a first optical member to make the primary diffracted beam a collimated beam, a beam deflecting means to deflect the collimated beam to make it a scanning beam, a second optical member to focus the scanning beam, a receiving surface positioned so that it is in a conjugate position with the acoustic optical modulator with respect to the first and the second optical members, and an aperture means positioned between the first optical member and the beam deflecting means and which restricts the beam in the direction of progression of the acoustic wave across the collimated beam, having a condenser lens which collects the laser beam emitted from the laser beam emitter in the acoustic optical modulator and in which an fθ lens is the second optical member.

45 citations

Journal ArticleDOI
TL;DR: The cutoff rate is derived for a digital communication system employing an optical carrier and direct detection and the coordinated design of the encoder, optical modulator, and demodulator is studied using the cutoff rate as a performance measure rather than the more commonly employed error probability.
Abstract: The cutoff rate is derived for a digital communication system employing an optical carrier and direct detection. The coordinated design of the encoder, optical modulator, and demodulator is then studied using the cutoff rate as a performance measure rather than the more commonly employed error probability. Modulator design is studied when transmitted optical signals are subject simultaneously to average-energy and peak-value constraints. Pulse-position modulation is shown to maximize the cutoff rate when the average-energy constraint predominates, and the best signals when the peak-value constraint predominates are identified in terms of Hadamard matrices. A time-sharing of these signals maximizes the cutoff rate when neither constraint dominates the other. Problems of efficient energy utilization, choice of input and output alphabet dimension, and the effect of random detector gain are addressed.

45 citations

Patent
11 Jul 2012
TL;DR: In this paper, a spatio-temporal directional light modulator is introduced to modulate the intensity, color and direction of the light it emits within an wide viewing angle.
Abstract: A spatio-temporal directional light modulator is introduced This directional light modulator can be used to create 3D displays, ultra-high resolution 2D displays or 2D/3D switchable displays with extended viewing angle The spatio-temporal aspects of this novel light modulator allow it to modulate the intensity, color and direction of the light it emits within an wide viewing angle The inherently fast modulation and wide angular coverage capabilities of this directional light modulator increase the achievable viewing angle, and directional resolution making the 3D images created by the display be more realistic or alternatively the 2D images created by the display having ultra high resolution

45 citations

Patent
Dominic Goodwill1
09 Sep 1999
TL;DR: In this article, a free space optical interconnect system having redundant elements of a transmitter and/or receiver and being tolerant to misalignments is provided, where the data to be transmitted is rerouted from the element which is misaligned to a redundant element selected along a direction associated with the direction of the misalignment so as to ensure data transmission through the system.
Abstract: A free space optical interconnect system having redundant elements of a transmitter and/or receiver and being tolerant to misalignments is provided. The system provides monitoring of a misalignment between the transmitter and receiver, including determining of a direction and amplitude of the misalignment. When the amplitude of the misalignment is exceeding a pre-determined threshold value, the data to be transmitted is re-routed from the element which is misaligned to a redundant element selected along a direction associated with the direction of the misalignment so as to ensure data transmission through the system. In an embodiment of the invention, monitoring of the misalignment and determining of the direction and the amplitude of the misalignment is performed by measuring of a position of a laser spot of a dedicated alignment laser on a dedicated detector. Optionally, redundant elements may be arranged into clusters, the number of clusters being redundant and the number of elements in each cluster being sufficient to accommodate the number of data channels to be transmitted. The elements of the system may be arranged into one-dimensional or two-dimensional arrays, or any other required pattern, the elements of the transmitter being optical emitters or optical modulators. The system described above is suitable for both uni-directional and bi-directional data transmission. A corresponding method for operating of such a system is also provided.

45 citations

Patent
Mario J. Paniccia1
13 Feb 2003
TL;DR: In this paper, an optical beam is generated with a gain medium disposed in a semiconductor substrate and an optical modulator is coupled to modulate the optical beam in response to a modulation signal.
Abstract: An optical transmit module. In one aspect of the present invention, an optical beam is generated with a gain medium disposed in a semiconductor substrate. A tunable Bragg grating also disposed in the semiconductor substrate may be optically coupled to the gain medium to tune an output wavelength of the optical beam. The semiconductor substrate further includes an optical modulator optically coupled to receive the optical beam. The optical modulator is coupled to modulate the optical beam in response to a modulation signal.

45 citations


Network Information
Related Topics (5)
Optical fiber
167K papers, 1.8M citations
91% related
Amplifier
163.9K papers, 1.3M citations
86% related
Semiconductor
72.6K papers, 1.2M citations
86% related
Laser
353.1K papers, 4.3M citations
85% related
Wafer
118K papers, 1.1M citations
83% related
Performance
Metrics
No. of papers in the topic in previous years
YearPapers
202342
2022154
2021166
2020289
2019311
2018325