PATENT CLAIM ANALYSIS

Application Number: 15774897
Application Type: Utility
Filing Date: 2018-05
Publication Date: 2018-11
Patent Classification: ["398", "183000"]

Abstract:
An optical transmitter includes: an optical modulator including an MZ interferometer, a drive signal input electrode, and a phase difference adjustment bias electrode; a drive amplifier; a phase difference adjustment bias voltage generator; a dithering unit that applies dithering of a predetermined frequency to an amplitude of a drive signal or to a half-wave voltage of the MZ interferometer; a controller unit that changes a phase difference adjustment bias voltage based on a modulation component of the frequency that is superimposed onto modulated light that is output from the optical modulator, to thereby bias the MZ interferometer to a null point; and a synchronous detection circuit that synchronously detects the modulation component of the frequency that is superimposed onto the modulated light. The controller unit changes the phase difference adjustment bias voltage such that a result of synchronous detection by the synchronous detection circuit becomes maximized or minimized. Whether the controller unit maximizes or minimizes the result of synchronous detection is determined by a difference between a phase of a referenced clock signal and a phase of the dithering, and does not depend on the amplitude of the drive signal.

Claim (Index 11):
A method for controlling a bias voltage in an optical transmitter, the optical transmitter comprising an optical modulator comprising an MZ interferometer comprising two optical waveguides, the method comprising the steps of:\n applying a drive signal that changes an optical phase of two optical signals, the two optical signals respectively propagating through the two optical waveguides; applying a phase difference adjustment bias voltage, the phase difference adjustment bias voltage adjusting the optical phase difference of the two signals by changing the optical phase of the two optical signals; applying dithering of a predetermined frequency to an amplitude of the drive signal or to a half-wave voltage of the MZ interferometer; changing the phase difference adjustment bias voltage based on an intensity modulation component of the frequency that is superimposed onto modulated light that is output from the optical modulator, to thereby bias the MZ interferometer to a null point; receiving the modulated light that is output from the optical modulator and converting it into an electric signal; and synchronously detecting the intensity modulation component of the frequency that is superimposed onto the converted electric signal, wherein the step of biasing comprises the step of changing the phase difference adjustment bias voltage such that a result of synchronous detection becomes maximized or minimized, to thereby bias the MZ interferometer to the null point, and whether the result of synchronous detection is maximized or minimized is determined by a difference between a phase of a referenced clock signal and a phase of the dithering, and does not depend on the amplitude of the drive signal.

Metadata:
- Claim Count in Document: 8.0
- Percentile: 93.0
- Lexical Diversity: 2.67105
- Patent Class: 398.0
- Transitional Phrase Type: open
- Component Type: 1
- Foreign Priority: True
- Related Applications: ['14934263', '15172289', '11275420', '13393101', '14575020']

Analysis Scores:
- 35 USC 101 Eligibility (BERT): 0.7036683143115583
- 35 USC 102 Novelty (BERT): 0.5161052893501696
- Combined Prediction Score: 0.6849120118154194
- Mean Citation Score: 272.431164
- Max Citation Score: 285.2637
- Similarity Product: 241.1531855066299

Labels:
- Claim Label 101: 1
- Claim Label 102: 0
- Claim Label 103: 1
- Claim Label 112: 1
- Combined Label: 0
- Label 101 Adjusted: 1

Dataset: test