We present the redshift catalogs for the X-ray sources detected in the Chandra Deep Field North ( CDF-N ) , the Chandra Large Area Synoptic X-ray Survey ( CLASXS ) , and the Chandra Lockman Area North Survey ( CLANS ) .
The catalogs for the CDF-N and CLASXS fields include redshifts from previous work , while the redshifts for the CLANS field are all new .
For fluxes above 10 ^ { -14 } ergs cm ^ { -2 } s ^ { -1 } ( 2 - 8 ~ { } keV ) we have redshifts for 76 % of the sources .
We extend the redshift information for the full sample using photometric redshifts .
The goal of the OPTX Project is to use these three surveys , which are among the most spectroscopically complete surveys to date , to analyze the effect of spectral type on the shape and evolution of the X-ray luminosity functions and to compare the optical spectral types with the X-ray spectral properties .

We also present the CLANS X-ray catalog .
The nine ACIS-I fields cover a solid angle of \sim 0.6 deg ^ { 2 } and reach fluxes of 7 \times 10 ^ { -16 } ergs cm ^ { -2 } s ^ { -1 } ( 0.5 - 2 ~ { } { keV } ) and 3.5 \times 10 ^ { -15 } ergs cm ^ { -2 } s ^ { -1 } ( 2 - 8 ~ { } { keV } ) .
We find a total of 761 X-ray point sources .
Additionally , we present the optical and infrared photometric catalog for the CLANS X-ray sources , as well as updated optical and infrared photometric catalogs for the X-ray sources in the CLASXS and CDF-N fields .

The CLANS and CLASXS surveys bridge the gap between the ultradeep pencil-beam surveys , such as the CDFs , and the shallower , very large-area surveys .
As a result , they probe the X-ray sources that contribute the bulk of the 2 - 8 ~ { } { keV } X-ray background and cover the flux range of the observed break in the log N - log S distribution .
We construct differential number counts for each individual field and for the full sample .