To provide a spectral element having characteristics of significant wavelength dispersion by using a thin film two-dimensional photonic crystal having the incident face and the exit face of light parallel to each other.
A thin film two-dimensional photonic crystal having a periodical repeated structure in two directions orthogonal with to each other is used for the optical element. When the above two directions of the periodical structure are denoted by Y-axis and Z-axis, two surfaces of the photonic crystal structure opposing to each other, perpendicular to the Z-axis, and parallel to the Y-axis are used as the incident face and the exit face of the light. The propagation direction of the beam incident to the incident face is controlled to be parallel to the Y-Z plane and at a specified tilt angle to the Z-axis.
KIKKO SHIGEO
OYA KAZUAKI
TSUNETOMO KEIJI
NARA MASATOSHI
