Oh boy... Lots of good info here. I can see there is some confusion - At the risk of making it worse, I'd like to try and resolve it, for the OP's benefit at least:
The "C" in "DAC" means "Copper". (Direct Attached Copper) - It has an SFP+ connector at both ends. There is nothing optical in it. The whole thing is called "twinax"; 2 wires with shielding. Those wires are electrically connected to contacts on the SFP+. They are not a transceiver, but use the shell of a transceiver to physically fit inside the SFP+ port. The lack of optical makes them useful for short runs, as they are cheap. It's copper the whole way through.
DAC:
When the OP said "I want optical" I suspect he may actually mean "I want to make use of the SFP+ ports on my equipment" - Not necessarily that he wants literal fiber optic. (This could be wrong)
There is something else called an "AOC" or "Active Optical Cable". They have bona-fide optical transceivers at each end (not just a shell like a DAC), but they are permanently connected, non-removable. The "wire" portion isn't a wire, nor is it copper - It's a glass fiber optic with light blasting through it. These work at longer distances.
A transceiver is an optical/electrical interface inside an SFP+ enclosure. Like the end of an AOC, but the fiber can be removed. You plug a fiber optic cable between these, with LC connectors, for example. The word "transceiver" means " bi-directional conversion of signal regimes", implying an electrical/optical interface. In radio, a transceiver is an RF/electrical interface - A transmitter and receiver in the same box.
Transceiver:
Some people refer to "AOCs" as a type of DAC - People say this, but it's not strictly correct because the C in DAC is "Copper". But people still say it, or they say "Active DAC", etc. It's a bit like saying "Koala Bears" or something - They're not really bears but the name is in common parlance.
Some people may also call the connector at the end of a purely-copper DAC a "transceiver" - Again, not strictly correct, there is no electrical/optical interface, it's just 2 wires soldered to a tiny board. But it's in common parlance to call them built-in transceivers.
Anyway, I hope this helps more than it causes additional confusion.