Gaussian laser beam diameter measurement using a quadrant photodiode

Tuck Wah Ng, S L Foo, H Y Tan

Research output: Contribution to journalArticleResearchpeer-review

12 Citations (Scopus)


Gaussian laser beam diameters are typically measured using knife-edges or gratings. Both require precise alignment with the photodiode placed after them from the laser source. In addition, beam diameter measurement in two orthogonal axes is only possible via rotation of the knife-edge or grating. Here, we report a novel measurement method that uses a relatively inexpensive and robust quadrant photodiode to circumvent the alignment requirement as well as allow two axes laser beam diameter measurement without rotation of any component. The theoretical basis of this approach is described and experimental results using it are presented. This method portends possibilities in the design of instrumentation that integrates Gaussian laser beam diameter measurement with laser beam tracking in a compact manner using fewer components.
Original languageEnglish
Article number065110
Number of pages3
JournalReview of Scientific Instruments
Issue number6
Publication statusPublished - 2005
Externally publishedYes

Cite this