Described herein are embodiments of squarylium compounds for use as filters in light-emitting and/or display devices. One problem of known quarylium dyes is that strong nucleophiles can attack the electron-deficient cyclobutene ring which can lead to a loss of the dye's colour. Another potential drawback with squaraine dyes can be their tendency to form aggregates, which can lead to a substantial broadening of their absorption bands. Use of the present compounds in filters address these problems. The squarylium compounds of the present invention have the following formulas: