
Front polariser on LCD has "sunburn"! In other words it has lost most of it's ability to polarise the incident light. Very common in 30+ year old Seikos- easy fix- simply cut a new piece of (non adhesive for M159) polarising material to fit over display and insert (don't forget to check the plane of polarisation before cutting!).
Material (about .003" is right) is available from quite a lot of sources- beware of the thin stuff being sold to check for glass stressing, usually too dark for watches.
Self adhesive polarising film can be used. but is much more difficult to use- the protective films rotate the apparent PoP so you have to compensate for this.