Device, method and apparatus for optical modulation using ferroelectric polymer liquid crystals

An optical modulation apparatus, comprising:

• an optical modulation device comprising a pair of electrodes and a ferroelectric having a spontaneous polarization and a glass transition point, said ferroelectric being disposed between the electrodes;
• means for writing in the ferroelectric by heating the ferroelectric at or above the glass transition point under application of an electric field to orient the spontaneous polarization to a prescribed direction and holding the prescribed direction of the spontaneous polarization below the glass transition point;
• and
• means for optically discriminating the prescribed direction of the spontaneous polarization as a difference in the birefringence of the ferroelectric held below the glass transition point.

An optical modulation apparatus, comprising:

• an optical modulation device including an optical modulation layer comprising an optical modulation compound having a birefringence, the optical modulation layer being set to an optical thickness capable of providing a multiple reflection state;
• optical modulation means for changing the optical thickness of the optical modulation layer to change the multiple reflection state of the layer;
• and
• means for illuminating the optical modulation layer with readout light to optically discriminate the multiple reflection state as a difference in quantity of reflected light.

An optical modulation method, comprising:

• providing an optical modulation device including an optical modulation layer comprising an optical modulation compound having a birefringence and capable of changing the birefringence in response to an electric field applied thereto, the optical modulation layer being set to an optical thickness capable of providing a multiple reflection state;
• changing the optical thickness of the optical modulation layer to change the multiple reflection state of the layer;
• and
• illuminating the optical modulation layer with readout light to optically discriminate the multiple reflection state as a difference in quantity of reflected light.

An optical modulation apparatus, comprising:

• an optical modulation device including an optical modulation layer comprising an optical modulation compound having a glass transition point and a refractive index anisotropy, the optical modulation layer being set to an optical thickness capable of providing a multiple reflection state;
• recording means for writing in the optical modulation layer at or above the glass transition point of the optical modulation compound and holding the resultant written state below the glass transition point, said recording means including optical modulation means for changing the optical thickness of the optical modulation layer to change the multiple reflection state of the optical modulation layer;
• and
• means for illuminating the optical modulation layer with readout light to optically discriminate the multiple reflection state as a difference in quantity of reflected light.

An optical modulation method, comprising:

• providing an optical modulation device including an optical modulation layer comprising an optical modulation compound having a glass transition point and a refractive index anisotropy, the optical modulation layer being set to an optical thickness capable of providing a multiple reflection state;
• a recording step for writing in the optical modulation layer at or above the glass transition point of the optical modulation compound and holding the resultant written state below the glass transition point, said recording step including a step for changing the optical thickness of the optical modulation layer to change the multiple reflection state of the optical modulation layer;
• and
• illuminating the optical modulation layer with readout light to optically discriminate the multiple reflection state as a difference in quantity of reflected light.

An optical modulation apparatus, comprising:

• an optical modulation device including an optical modulation layer comprising an optical modulation compound which has a glass transition point and a refractive index anisotropy and is capable of changing its refractive index anisotropy in response to an electric field applied thereto, the optical modulation layer being set to an optical thickness capable of providing a multiple reflection state;
• means for irradiating the optical modulation layer with writing light and applying an electric field of one polarity across the optical modulation layer to change the multiple reflection state of the optical modulation layer, thus writing in the optical modulation layer;
• and
• means for irradiating the optical modulation layer with erasure light having a plane of polarization different from that of the writing light and applying an electric field of the opposite polarity across the optical modulation layer to again change the multiple reflection state of the optical modulation layer, thus erasing the optical modulation layer.

An optical modulation apparatus, comprising:

• an optical modulation device including an optical modulation layer comprising an optical modulation compound which has a glass transition point and a refractive index anisotropy and is capable of changing its refractive index anisotropy in response to an electric field applied thereto, the optical modulation layer being set to an optical thickness capable of providing a multiple reflection state;
• means for irradiating the optical modulation layer with writing light and applying an electric field of one polarity across the optical modulation layer to change the multiple-reflection state of the optical modulation layer, thus writing in the optical modulation layer;
• and
• means for irradiating the optical modulation layer with erasure light having a wavelength different from that of the writing light and applying an electric field of the opposite polarity across the optical modulation layer to again change the multiple reflection state of the optical modulation layer, thus erasing the optical modulation layer.

An optical modulation apparatus, comprising:

• an optical modulation device including an optical modulation layer comprising an optical modulation compound which has a glass transition point and a refractive index anisotropy and is capable of changing its refractive index anisotropy in response to an electric field applied thereto, the optical modulation layer being set to an optical thickness capable of providing a multiple reflection state;
• means for irradiating the optical modulation layer with writing light and applying an electric field of one polarity across the optical modulation layer to change the multiple reflection state of the optical modulation layer, thus writing in the optical modulation layer;
• and
• means for irradiating the optical modulation layer with erasure light having a wavelength and a plane of polarization different from those of the writing light and applying an electric field of the opposite polarity across the optical modulation layer to again change the multiple reflection state of the optical modulation layer, thus erasing the optical modulation layer.