Laser Diode Drive Circuit With Preliminary Current for Low Latency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional light emission drive circuits for laser diodes become complex due to the need to supply multiple overshoot currents, complicating the configuration and increasing light emission latency time.
Innovation Solution
A light emission drive circuit that includes a light emission current wire, a preliminary current wire, and switches to control these currents, with a preliminary current flowing before the light emission period to excite the inductance component of the light emission current wire, thereby simplifying the configuration and reducing latency time.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of time
If multiple overshoot currents are supplied to the laser diode to shorten light emission latency time, then the light emission latency time is reduced, but the drive circuit becomes complicated
Solution Approach 1:
The patent applies preliminary action by flowing a preliminary current through the light emission current wire before the light emission period to excite the inductance component in advance. This pre-excitation of the inductance reduces the time required for the light emission current to rise when the actual emission begins, thereby shortening the light emission latency time without requiring multiple complex overshoot current circuits
Solution Approach 2:
The patent changes the temporal parameter of current flow by introducing a preliminary current that flows before the light emission period. This parameter change in the timing and sequence of current application allows the inductance to be pre-excited, reducing the rising time of the light emission current and simplifying the overall drive circuit compared to using multiple simultaneous overshoot currents
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The proposed solution effectively shortens the light emission latency time by exciting the parasitic inductances of the wires with a preliminary current, allowing for faster rising of the light emission current and simplifying the device configuration.
Implementation Method 1
a preliminary current wire configured to flow, in the light emission current wire, a preliminary current for exciting an inductance component of the light emission current wire before a light emission period
Data Source
AI summary
A configuration of a light emission device that shortens a light emission latency time of a light emitting element is simplified.A light emission drive circuit includes a light emission current wire, a light emission current switch, a preliminary current wire, and a preliminary current switch. The light emission current wire flows a light emission current for causing a light emitting element to emit light, is the light emitting element. The light emission current switch is connected to the light emission current wire, and controls the light emission current. The preliminary current wire flows, in the light emission current wire, a preliminary current for exciting an inductance component of the light emission current wire before a light emission period being a period in which the light emission current flows in the light emitting element. The preliminary current switch is connected to the preliminary current wire, and controls the preliminary current.