TUNABLE POLYMER DISPERSED LIQUID CRYSTAL DOUBLET PRISM
A camera system includes an image sensor assembly and a tunable optical element. The tunable optical element is a doublet prism including one polymer dispersed liquid crystal layer. The doublet prism is tunable by applying an electric field to the optical element via a control element. The control element applies a voltage differential to the optical element inducing an electric field which changes the polarization of the PDLC within the optical element. The refractive index of the doublet prism is dependent on the polarization of the liquid crystals within the optical element. Applying the electric field to the tunable element changes the optical properties of the doublet prism.
1 . A camera system including
an image sensor assembly configured to capture images, the image sensor assembly centered about an optical axis;
a tunable optical element for focusing light onto the image sensor assembly, the tunable optical element substantially rectangular having a bottom side and a top side centered about the optical axis comprising:
a first layer of a first material, the first layer having a first refractive index associated with the first material,
a second layer of a second material, wherein a polarization of the second material is controllable by an applied electric field, wherein the second layer has a second refractive index controllable by the polarization of the second material,
wherein the first and second layers are layered in a layer stack of the tunable optical element,
wherein the first and second layer have a triangular shaped cross sections forming a right triangular prism in each of the layers,
a first control element coupled to the tunable optical element for applying a voltage differential to the first and second layers, the voltage differential creating the electric field controlling the second refractive index of the second layer of the tunable optical element, and
wherein the hypotenuses of the right triangular prisms are in contact with one another, the long edge of each triangular prism is coupled to the first control element and the short edges of the right triangular prisms are parallel to the optical axis.
2 . The camera system of claim 1 wherein the second material is a tunable polymer dispersed liquid crystal.
3 . The camera system of claim 1 wherein the second material comprises a first state and a second state, the first state configuring the tunable element to transmit light and the second state configured to alter transmitted light.
4 . The camera system of claim 3 , wherein the applied electric field toggles the second material from the first state to the second state.
5 . The camera system of claim 3 , wherein the polarization of the second material in the first state is a first value and the polarization of the second material in the second state is a second value.
6 . The camera system of claim 1 wherein the first control element is a pair or electrodes coupled to opposing surfaces of the tunable optical element.
7 . The camera system of claim 3 , wherein a first voltage is applied to a first electrode of the pair and a second voltage is applied to a second electrode of the pair.
8 . The camera system of claim 1 wherein applying the electric field changes the optical path of the transmitted light.
9 . The camera system of claim 1 wherein applying an electric field to the tunable element affects the dispersion of the transmitted light.
10 . The camera system of claim 1 comprising a lens tube comprising optical elements, the tunable element one of the optical elements of the lens tube.
11 . A tunable optical element comprising
a first layer of a first material, the first layer having a first refractive index associated with the first material;
a second layer of a second material, wherein a polarization of the second material is controllable by an applied electric field, wherein the second layer has a second refractive index controllable by the polarization of the second material;
a first control element coupled to the tunable optical element for applying a voltage differential to the first and second layers, the voltage differential creating the electric field controlling the second refractive index of the second layer of the tunable optical element;
wherein the first and second layers are layered in a layer stack of the tunable optical element,
wherein the first and second layer have a triangular shaped cross section forming a right triangular prism in each of the layers;
wherein the tunable optical element is substantially rectangular having a bottom side, and a top side centered about an optical axis; and
wherein the hypotenuses of the right triangular prisms are in contact with one another, the long edge of each triangular prism is coupled to the first control element and the short edges of the right triangular prisms are parallel to the optical axis.
12 . The tunable optical element of claim 11 wherein the second material is controllable between a first state and a second state, the first state configuring the tunable element to transmit light and the second state configured to alter the transmitted light.
13 . The tunable optical element of claim 11 wherein the second material is a tunable polymer dispersed liquid crystal.
14 . The tunable optical element of claim 11 wherein the first control element is a pair or electrodes coupled to opposing surfaces of the tunable optical element.
15 . The tunable optical element of claim 11 comprising a lens tube comprising optical elements, the tunable element one of the optical elements of the lens tube.
16 . A camera system including
an image sensor assembly configured to capture images, the image sensor assembly centered about an optical axis;
a tunable optical element for focusing light onto the image sensor assembly, the tunable optical element substantially rectangular having a bottom side, and a top side centered about the optical axis comprising:
a first layer of a first material, the first layer having a first refractive index associated with the first material,
a second layer of a second material, wherein the second layer has a second refractive index controllable by an applied electric field,
wherein the first and second layers are layered in a layer stack of the tunable optical element,
wherein the first and second layer have a triangular shaped cross sections forming a right triangular prism of each of the layers,
a first control element coupled to the tunable optical element for applying a voltage differential to the first and second layers, the voltage differential creating the electric field controlling the second refractive index of the second layer of the tunable optical element, and
wherein the hypotenuses of the right triangular prisms are in contact with one another, the long edge of each triangular prism is coupled to the first control element and the short edges of the right triangular prisms are parallel to the optical axis.
17 . The camera system of claim 16 wherein the second material is controllable between a first state and a second state, the first state configuring the tunable element to transmit light and the second state configured to alter the transmitted light.
18 . The camera system of claim 16 wherein the second material is a tunable polymer dispersed liquid crystal.
19 . The camera system of claim 16 wherein the first control element is a pair or electrodes coupled to opposing surfaces of the tunable optical element.
20 . The camera system of claim 16 comprising a lens tube comprising optical elements, the tunable element one of the optical elements of the lens tube.