Optical lens structure and control system for maintaining a selected constant level of transmitted light at a wearer's eyes

An optical device for controlling an amount of light received at a wearer's eye, the optical device comprising:

• a) a frame;
• b) a lens structure mounted in the frame, the lens structure including;
• i) a first lens;
• ii) a second lens;
• iii) a transmission layer disposed between the first lens and the second lens, the transmission layer having a electro-optic property in response to and in proportion to an electric field placed across the transmission layer such that the transmission layer determines the amount of light that passes through the lens structure;
• and
• iv) electrical terminals electrically connected across the transmission layer to produce an electric field across the transmission layer;
• c) a sensor mounted behind the second lens to develop a signal proportional to the light passing through the lens structure;
• d) a control circuit electrically connected to the sensor, the control circuit comparing the signal to a maximum transmission level and a minimum transmission level to ensure that the light passing through the lens structure is within a desired range;
• and
• e) a power supply electrically connected to the electrical terminals and controlled by the control circuit, the power supply used to add and remove charge from the lens structure in response to the control circuit.

An optical device for controlling an amount of light received at a wearer's eye, the optical device comprising:

• a) a frame;
• b) a lens structure mounted in the frame, the lens structure including;
• i) a first polarizer having a first plane of polarization to receive light incident on the optical device and to transmit polarized light, the polarized light being polarized in the first plane of polarization;
• ii) a transmission layer adjacent the first polarizer to receive the polarized light, the transmission layer having an electro-optic property such that the transmission layer rotates the polarized light in response to and in an amount proportional to an electrical field placed across the transmission layer;
• iii) a second polarizer adjacent the transmission layer opposite the first polarizer and having a second plane of polarization, the second polarizer to receive the polarized light rotated by the transmission layer and to transmit a percentage of the polarized light, the percentage corresponding to the amount of rotation and the second plane of polarization;
• and
• iv) electrical terminals connected to the transmission layer, the electrical terminals capable of holding a charge, the charge inducing the electric field across the transmission layer;
• c) a sensor mounted on the second lens opposite the transmission layer, the sensor generating a signal proportional to the percentage of polarized light transmitted by the second polarizer;
• d) a high voltage power supply and electrically connected to the electrical terminals, the high voltage power supply used to control the charge on the electrical terminals by placing a voltage across the electrical terminals, wherein the voltage is continuously variable up to a maximum safe voltage;
• and
• e) a control circuit and electrically connected to the sensor and the high voltage power supply, the control circuit receiving the signal from the sensor and causing the high voltage power supply to add or remove charge as necessary when the signal from the sensor is outside a desired operating range.

An optical device for maintaining a preset transmission level of light at a wearer's eye, the eyewear apparatus comprising:

• a) a frame including a left earpiece and a right earpiece and a seal, the left earpiece, the right earpiece and the seal preventing light from reaching the wearer's eye other than through the eyewear apparatus;
• b) a lens structure mounted in the frame and including a first and second lens, each of the first and second lenses formed by
• i) a first polarizer mounted in frame and having a first plane of polarization, wherein the first polarizer receives ambient light and transmits polarized light;
• ii) a lead-lanthanum zirconate/titanate (PLZT) layer mounted in the frame adjacent the first polarizer, the (PLZT) layer including a plurality of filaments such that an electric field is developed across the (PLZT) layer when a voltage is applied to the plurality of filaments, wherein the (PLZT) layer receives the polarized light, rotates the polarized light in an amount proportional to the electric field, and transmits rotated polarized light;
• iii) a second polarizer mounted in the frame adjacent to the (PLZT) layer opposite the first polarizer, the second polarizer having a second plane of polarization, wherein the second polarizer receives the rotated polarized light from the (PLZT) layer and transmits the preset light level to the wearer's eye;
• and
• iv) electrical terminals electrically connected to the plurality of filaments;
• c) a sensor mounted on the second polarizer of the first lens, wherein the sensor develops a signal proportional to the preset light level transmitted by the second polarizer of the first lens;
• d) a high voltage power supply mounted in the frame and electrically connected to the electrical terminals, wherein the high voltage power supply supplies a continuously variable voltage to the electrical terminals and a maximum safe voltage of at least 500 volts;
• e) a control circuit mounted in the frame, the control circuit being electrically connected to the sensor and the high voltage power supply, wherein the control circuit causes the high voltage power supply to alter the continuously variable voltage across the electrical terminals in response to the signal from the sensor corresponding to the preset light level having strayed outside a preset transmission range.