US 12,366,822 B2
Radial polarization conversion component, azimuthal polarization conversion component and manufacturing method thereof
Jing Heng Chen, Taichung (TW); Chien Yuan Han, New Taipei (TW); Fan Hsi Hsu, Hsinchu (TW); Kun-Huang Chen, Taichung (TW); Chien Hung Yeh, Taichung (TW); and Hung Lung Tseng, Taichung (TW)
Assigned to Feng Chia University, Taichung (TW)
Filed by FENG CHIA UNIVERSITY, Taichung (TW)
Filed on May 24, 2022, as Appl. No. 17/752,285.
Claims priority of application No. 110118904 (TW), filed on May 25, 2021.
Prior Publication US 2022/0382212 A1, Dec. 1, 2022
Int. Cl. G03H 1/02 (2006.01); G02B 27/28 (2006.01); G03H 1/04 (2006.01)
CPC G03H 1/0248 (2013.01) [G02B 27/286 (2013.01); G03H 1/0402 (2013.01); G03H 2223/18 (2013.01); G03H 2223/24 (2013.01)] 2 Claims
OG exemplary drawing
 
1. A method for manufacturing a radial polarization conversion component comprising the steps of:
placing a holographic recording material between two right-angle prisms, wherein the holographic recording material is divided into at least four sector-shaped areas and is partially shielded, and only one of the sector-shaped areas is exposed each time;
allowing a recording light with a wavelength of 300 to 850 nm to pass through an electronic shutter, a filter and a collimating lens, the recording light being incident on one of the right-angle prisms, passing through the exposed sector-shaped area of the holographic recording material and the other right-angle prism and being reflected by a reflector to form an object light, the recording light and the object light interfering in the exposed sector-shaped area of the holographic recording material;
rotating the holographic recording material to expose the other sector-shaped areas one by one and repeating the above steps for construction; wherein the right-angle prisms each have a base angle, the relationship between the base angle and the diffraction angle caused by the incident reconstruction light is:

OG Complex Work Unit Math
where, θd is the diffraction angle when the reconstruction light is incident on the holographic recording material;
θp1 is the base angle;
λ1 is the wavelength of the recording light;
λ2 is the wavelength of the reconstruction light;
nf1 is the index of refraction of the holographic recording material corresponding to the recording light;
nf2 is the index of refraction of the holographic recording material corresponding to the reconstruction light;
np is the index of refraction of the right-angle prism corresponding to the recording light;
d1 is the thickness of the holographic recording material before exposure;
d2 is the thickness of the holographic recording material after exposure; and
wherein the radial polarization conversion component includes a complete circular volume hologram, the volume hologram is radially divided into at least four sector-shaped areas, and the sector-shaped areas each enable an incident reconstruction light with a wavelength of 200 to 600 nm to have a diffraction angle of 48.19 degrees or angles within a few degrees of 85 degrees.