Optical device having a wide field-of-view for multicolor images

A method of manufacturing a diffractive optical element for guiding a light having a color spectrum characterized by a plurality of wavelengths longer than a shortest wavelength, λB, and shorter than a longest wavelength λR, the light striking the diffractive optical element at an angle greater than a first field-of-view angle, α−FOV, and smaller than a second field-of-view angle, α+FOV, the method comprising:

• (a) determining a linear grating pitch, d, so as to allow total internal reflection of a light having wavelength of λB and a striking angle of α−FOV;
• (b) determining a minimal index of refraction, nMIN, so as to allow total internal reflection of a light having wavelength of λR and a striking angle of α+FOV;
• and
• (c) forming a linear grating characterized by said grating pitch, d, in a light-transmissive substrate characterized by an index of refraction, ns, wherein said ns being larger than said nMIN.

A method of manufacturing an optical device for transmitting a light having a color spectrum characterized by a plurality of wavelengths longer than a shortest wavelength, λB and shorter than a longest wavelength λR, the light striking the optical device at an angle greater than a first field-of-view angle, α−FOV, and smaller than a second field-of-view angle, α+FOV, the method comprising:

• (a) determining a linear grating pitch, d, so as to allow total internal reflection of a light having wavelength of λB and a striking angle of α−FOV;
• (b) determining a minimal index of refraction, nMIN, so as to allow total internal reflection of a light having wavelength of λR and a striking angle of α+FOV;
• and
• (c) positioning a light-transmissive substrate and forming therein a first diffractive optical element and a second diffractive optical element laterally displaced from said first diffractive optical element;
• wherein said first and said second diffractive optical elements are linear gratings characterized by said grating pitch, d, and said light-transmissive substrate is characterized by an index of refraction, ns, which is larger than said nMIN.