In theory, We know we can get the interference pattern with coherent source as Laser, and we can not obtain the interference pattern with incoherent source. However,
Has anyone done Young double slits experiment in where using many different kinds of light source such as: Monochromatic LED, Phosphor converted white LED, incandescent lamp .etc? Can you share some your experiment result or any publication?
Thanks a lot.
Seeing fringes in Young's double slit experiment should be possible using all of those sources, if the spatially incoherent source is first filtered by a pinhole. This last bit is actually the Van Cittert-Zernike theorem in practice. In a statistical optics class I taught this past spring, I formed fringes in a Young's experiment using a "monochromatic" LED (the linewidth was 30 nm). When the pinhole was completely open, no fringes were formed; when the pinhole was closed to less than 2 mm, the fringes became visible.
With narrowband LEDs you may be able to see a limited number of fringes:
https://physics.stackexchange.com/questions/201019/interference-of-led-lights
It is possible to perform the Young's double pinhole experiment with any type of source and get some interference (in principle), but the device does not work correctly for broadband light in its classical form. For this it needs to be modified, either in the spirit of https://www.osapublishing.org/oe/abstract.cfm?uri=oe-21-4-4061 or by spectrally resolving the interference pattern with an imaging spectrometer.
Also, it is quite important to understand that the double pinhole experiment with static pinholes does not yield information on the complete spatial coherence. In order to measure the complete spatial coherence function, you would need a device with moving pinholes, like it has been done in this thesis: http://epublications.uef.fi/pub/urn_isbn_978-952-61-1535-1/urn_isbn_978-952-61-1535-1.pdf
Here's one paper directly observe the interference pattern from incoherent light.
"Spatial Interference: From Coherent to Incoherent " Phys. Rev. Lett. 102, 073904 (2009).
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.102.073904
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