The present invention discloses an improved optical device having at least
a first and second optical components. The optical device further
includes a first extending tube securely attached to the first and second
optical components as a first building block wherein the first and second
optical components are aligned and position adjusted in the
position-holding-and-fixing means and securely attached thereto by a
room-temperature UV curable epoxy UV cured at room temperature. The
optical device then further assembled using a step-by-step building block
assembling process with more building blocks assembled by optical
components similar to the first building block described above. In other
preferred embodiment, the first and second optical components held in the
extending tube having a pre-aligned dihedral angle between the first and
second optical components.