Methods for testing optical transmitter components
View Patent ↗Methods for testing optical components, such as laser diodes or light emitting diodes, that are manufactured for use in optical transmitters or transceivers. The testing methods are performed using a true RMS conversion circuit in a test apparatus. The testing methods are performed by receiving an optical signal with AC and DC components from the optical component that is to be tested. The optical signal is converted to an electrical signal, and the AC and DC components of the electrical signal are separated. An RMS circuit of the test apparatus converts the AC component of the electrical signal to a DC function of the RMS value of the AC component of the electrical signal. This testing method can be used to determine whether optical components are suitable for use by customers or in products.
1. A method of testing an optical component, comprising:
receiving an optical signal from an optical component, the optical signal including AC and DC components;
converting the optical signal to an electrical signal;
separating AC and DC components of the electrical signal, wherein separating the AC and DC components of the electrical signal comprises:
using a first matching network of the test apparatus, receiving a high output of a differential output of an amplifier associated with the optical receiver of the test apparatus;
using a second matching network of the test apparatus, receiving a low output of the differential output of the amplifier; and
using a first filter associated with the first matching network and a second filter associated with the second matching network to separate the AC component and the DC component;
converting the AC component of the electrical signal to a function of the RMS value of the AC component of the electrical signal; and
providing the function of the RMS value to a data acquisition system.
2. The method of claim 1 , further comprising performing calibration by comparing the function of the RMS value to a calibrated RMS value of the AC portion of the electrical signal.
3. The method of claim 2 , further comprising compensating for a difference that shows a miscalibration between the function of the RMS value and the calibrated RMS value of the AC portion of the electrical signal.
4. The method of claim 1 , wherein converting the AC component of the electrical signal to a function of the RMS value of the AC component of the electrical signal comprises converting the AC component to a DC function of the RMS value.
5. The method of claim 4 , wherein converting the AC component to a DC function of the RMS value is performed using an RiVIS conversion circuit of a test apparatus.
6. The method of claim 1 , wherein the optical component comprises one of a laser diode and a light emitting diode.
7. The method of claim 6 , wherein receiving the optical signal is performed using an optical receiver of a test apparatus.
8. The method of claim 7 , further comprising controlling the optical component using a transmitter source that is connected to the optical component and provides an AC supply and a DC supply to the optical component during testing.
9. The method of claim 8 , wherein converting the optical signal to an electrical signal comprises receiving the optical signal using an optical receiver of the test apparatus.
10. The method of claim 6 , further comprising determining, as a result of testing the optical component, determining whether the optical component is defective.
11. The method of claim 6 , further comprising, as a result of testing the optical component, sorting the optical component into one of a plurality of groups of different-rated values.
12. The method of claim 6 , further comprising determining, as a result of testing the optical component, whether the optical component is to be included in an optical transceiver.
13. The method of claim 1 , further comprising, as a result of testing the optical component, plotting the amount of optical energy produced by the optical component as a function of the amount of current used to drive the optical component.
14. The method of claim 1 , further comprising, as a result of testing the optical component, determining the amount of noise produced by the optical component.
15. The method of claim 1 , wherein the method is performed on a single test board.