Actually, a small clarification is needed here. There were actually two sub-classes of the Essex class. They were divided into "short" hull, and "long" hull designs. While all are generally refered to as "Essex" class, only the short hull models were true Essex class as designed. The long hull versions were unofficially refered to as "Ticonderoga" class, but you wont be wrong calling them Essex class.
CV-9 through -13, -16 through -18, -20, -31, were short hull version.
CV-14, -15, -19, -21, -32, -33 through -40, -45, -46, and -47 were long hull version. The hulls were 68 feet longer than the short hull.
Only early-built short hulls recieved the hangar deck catapult, and in March 1943 all were removed in favor of a second flight deck installation.
And now back to our original story, about the IJN Kaga., yeah, that's the elevator in the photo.