" optical encoder where two encoder wheel are deployed and are displaced phy and produce phase shifted pulse(they are generally used for direction sensing along with displace sens)."

Known as encoders with quadrature output. These produce two pulses A and B with a phase difference of 90 deg angle.

"Using SET/RESST LOGIC simi to RS Flip-flop problem of multi pulse during trans could easily be solved."

No. This transition bounce in encoders is a devil to contend with and cannot be solved by the simple method described by you. You have to use a Quadrature Decoder cum Counter IC like the HCTL 2020. In fact if you search this forum for "encoders" you can see scores of postings discussing this very issue.

Raghu