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US 10,802,356 B2Granted
Touch screen for privacy display
AssigneeRealD Spark, LLC
InventorsJonathan Harrold, Graham J. Woodgate
Life of this patent
Estimating the term…
Abstract
A display comprises a polarised output spatial light modulator, switchable liquid crystal retarder, absorbing polariser and touch panel electrodes. The electrodes of the switchable liquid crystal retarder shield the touch panel electrodes from the electrical noise of the spatial light modulator addressing. The touch panel control and sensing may be synchronised with the driving signal of the switchable liquid crystal retarder. The touch panel may be operated independently of the timing of the data addressing of the spatial light modulator.
Claims31
A touch input display device comprising:
- a spatial light modulator (SLM) arranged to output light;
- a display polariser arranged on the output side of the SLM, wherein the display polariser is a linear polariser;
- an additional polariser arranged on the output side of the display polariser wherein the additional polariser is a linear polariser;
- a switchable liquid crystal retarder comprising a layer of liquid crystal material arranged between the display polariser and the additional polariser, wherein the switchable liquid crystal retarder is a polar control retarder that is arranged, in a switchable state of the switchable liquid crystal retarder, simultaneously to introduce no net relative phase shift to orthogonal polarisation components of light passed by the display polariser along an axis along a normal to the plane of the switchable liquid crystal retarder and introducing a relative phase shift to orthogonal polarisation components of light passed by the display polariser along an axis inclined to a normal to the plane of the switchable liquid crystal retarder;
- switchable retarder control electrodes arranged to apply a voltage for controlling the state of the switchable liquid crystal retarder;
- at least one touch electrode array arranged in a layer on the output side of the switchable retarder control electrodes;
- and
- input and output transparent support substrates, the layer of liquid crystal material being arranged between the input and output transparent support substrates, and the at least one touch electrode array being arranged between the switchable retarder control electrodes and the output transparent support substrate.
5 more elements
A touch input display device comprising:
- a spatial light modulator (SLM) arranged to output light;
- a display polariser arranged on the output side of the SLM, wherein the display polariser is a linear polariser;
- an additional polariser arranged on the output side of the display polariser wherein the additional polariser is a linear polariser;
- a switchable liquid crystal retarder comprising a layer of liquid crystal material arranged between the display polariser and the additional polariser, wherein the switchable liquid crystal retarder is a polar control retarder that is arranged, in a switchable state of the switchable liquid crystal retarder, simultaneously to introduce no net relative phase shift to orthogonal polarisation components of light passed by the display polariser along an axis along a normal to the plane of the switchable liquid crystal retarder and introducing a relative phase shift to orthogonal polarisation components of light passed by the display polariser along an axis inclined to a normal to the plane of the switchable liquid crystal retarder;
- switchable retarder control electrodes arranged to apply a voltage for controlling the state of the switchable liquid crystal retarder;
- at least one touch electrode array arranged in a layer on the output side of the switchable retarder control electrodes;
- and
- a control system, wherein the control system is arranged to apply a drive voltage to the switchable retarder control electrodes for controlling the switchable liquid crystal retarder, and the control system is arranged to address the at least one touch electrode array for capacitive touch sensing, and wherein the drive voltage has a waveform including periods where the drive voltage is constant, and the control system is arranged to address the at least one touch electrode array during at least one of the periods where the drive voltage is constant.
5 more elements
A touch input display device comprising:
- a spatial light modulator (SLM) arranged to output light;
- a display polariser arranged on the output side of the SLM, wherein the display polariser is a linear polariser;
- an additional polariser arranged on the output side of the display polariser wherein the additional polariser is a linear polariser;
- a switchable liquid crystal retarder comprising a layer of liquid crystal material arranged between the display polariser and the additional polariser, wherein the switchable liquid crystal retarder is a polar control retarder that is arranged, in a switchable state of the switchable liquid crystal retarder, simultaneously to introduce no net relative phase shift to orthogonal polarisation components of light passed by the display polariser along an axis along a normal to the plane of the switchable liquid crystal retarder and introducing a relative phase shift to orthogonal polarisation components of light passed by the display polariser along an axis inclined to a normal to the plane of the switchable liquid crystal retarder;
- switchable retarder control electrodes arranged to apply a voltage for controlling the state of the switchable liquid crystal retarder;
- at least one touch electrode array arranged in a layer on the output side of the switchable retarder control electrodes;
- and
- at least one passive retarder arranged between the switchable liquid crystal retarder and the additional polariser, wherein the at least one passive retarder comprises a pair of passive uniaxial retarders having optical axes in the plane of the passive uniaxial retarders that are crossed, and wherein the at least one touch electrode array comprises a pair of touch electrode arrays formed on facing surfaces of respective ones of the pair of passive uniaxial retarders, and said at least one dielectric layer comprises at least one additional layer arranged between the pair of passive uniaxial retarders.
5 more elements
A touch input display device comprising:
- a spatial light modulator (SLM) arranged to output light;
- a display polariser arranged on the output side of the SLM, wherein the display polariser is a linear polariser,
- an additional polariser arranged on the output side of the display polariser wherein the additional polariser is a linear polariser;
- a switchable liquid crystal retarder comprising a layer of liquid crystal material arranged between the display polariser and the additional polariser, wherein the switchable liquid crystal retarder is a polar control retarder that is arranged, in a switchable state of the switchable liquid crystal retarder, simultaneously to introduce no net relative phase shift to orthogonal polarisation components of light passed by the display polariser along an axis along a normal to the plane of the switchable liquid crystal retarder and introducing a relative phase shift to orthogonal polarisation components of light passed by the display polariser along an axis inclined to a normal to the plane of the switchable liquid crystal retarder;
- switchable retarder control electrodes arranged to apply a voltage for controlling the state of the switchable liquid crystal retarder;
- at least one touch electrode array arranged in a layer on the output side of the switchable retarder control electrodes, wherein the at least one touch electrode array comprises a pair of touch electrode arrays arranged in layers separated by at least one dielectric layer;
- and
- at least one passive retarder arranged between the switchable liquid crystal retarder and the additional polariser, wherein each of the pair of touch electrode arrays are formed on a respective surface of the passive retarder in the case that the display device comprises one passive retarder or a respective surface of one of the passive retarders in the case that the display device comprises more than one passive retarder.
5 more elements
A touch input display device comprising:
- a spatial light modulator (SLM) arranged to output light;
- a display polariser arranged on the output side of the SLM, wherein the display polariser is a linear polariser;
- an additional polariser arranged on the output side of the display polariser wherein the additional polariser is a linear polariser;
- a switchable liquid crystal retarder comprising a layer of liquid crystal material arranged between the display polariser and the additional polariser, wherein the switchable liquid crystal retarder is a polar control retarder that is arranged, in a switchable state of the switchable liquid crystal retarder, simultaneously to introduce no net relative phase shift to orthogonal polarisation components of light passed by the display polariser along an axis along a normal to the plane of the switchable liquid crystal retarder and introducing a relative phase shift to orthogonal polarisation components of light passed by the display polariser along an axis inclined to a normal to the plane of the switchable liquid crystal retarder;
- switchable retarder control electrodes arranged to apply a voltage for controlling the state of the switchable liquid crystal retarder;
- at least one touch electrode array arranged in a layer on the output side of the switchable retarder control electrodes, wherein the at least one touch electrode array comprises a pair of touch electrode arrays arranged in layers separated by at least one dielectric layer;
- and
- at least one passive retarder arranged between the switchable liquid crystal retarder and the additional polariser, wherein said at least one dielectric layer comprises the passive retarder in the case that the display device comprises one passive retarder or comprises at least one of the passive retarders in the case that the display device comprises more than one passive retarder.
5 more elements
A touch input display device comprising:
- a spatial light modulator (SLM) arranged to output light;
- a display polariser arranged on the output side of the SLM, wherein the display polariser is a linear polariser;
- an additional polariser arranged on the output side of the display polariser wherein the additional polariser is a linear polariser;
- a switchable liquid crystal retarder comprising a layer of liquid crystal material arranged between the display polariser and the additional polariser, wherein the switchable liquid crystal retarder is a polar control retarder that is arranged, in a switchable state of the switchable liquid crystal retarder, simultaneously to introduce no net relative phase shift to orthogonal polarisation components of light passed by the display polariser along an axis along a normal to the plane of the switchable liquid crystal retarder and introducing a relative phase shift to orthogonal polarisation components of light passed by the display polariser along an axis inclined to a normal to the plane of the switchable liquid crystal retarder;
- switchable retarder control electrodes arranged to apply a voltage for controlling the state of the switchable liquid crystal retarder;
- at least one touch electrode array arranged in a layer on the output side of the switchable retarder control electrodes, wherein the at least one touch electrode array comprises a pair of touch electrode arrays arranged in layers separated by at least one dielectric layer;
- and
- at least one passive retarder arranged between the switchable liquid crystal retarder and the additional polariser, wherein the display device comprises more than one passive retarder and said at least one dielectric layer comprises at least two passive retarders.
5 more elements
A touch input display device comprising:
- a spatial light modulator (SLM) arranged to output light;
- a display polariser arranged on the output side of the SLM, wherein the display polariser is a linear polariser;
- an additional polariser arranged on the output side of the display polariser wherein the additional polariser is a linear polariser;
- a switchable liquid crystal retarder comprising a layer of liquid crystal material arranged between the display polariser and the additional polariser, wherein the switchable liquid crystal retarder is a polar control retarder that is arranged, in a switchable state of the switchable liquid crystal retarder, simultaneously to introduce no net relative phase shift to orthogonal polarisation components of light passed by the display polariser along an axis along a normal to the plane of the switchable liquid crystal retarder and introducing a relative phase shift to orthogonal polarisation components of light passed by the display polariser along an axis inclined to a normal to the plane of the switchable liquid crystal retarder;
- switchable retarder control electrodes arranged to apply a voltage for controlling the state of the switchable liquid crystal retarder;
- at least one touch electrode array arranged in a layer on the output side of the switchable retarder control electrodes, wherein the at least one touch electrode array comprises a pair of touch electrode arrays arranged in layers separated by at least one dielectric layer;
- and
- at least one passive retarder arranged between the switchable liquid crystal retarder and the additional polariser, wherein said at least one dielectric layer comprises at least one additional layer that is not a retarder.
5 more elements
A touch input display device comprising:
- a spatial light modulator (SLM) arranged to output light;
- a display polariser arranged on the output side of the SLM, wherein the display polariser is a linear polariser;
- an additional polariser arranged on the output side of the display polariser wherein the additional polariser is a linear polariser;
- a switchable liquid crystal retarder comprising a layer of liquid crystal material arranged between the display polariser and the additional polariser, wherein the switchable liquid crystal retarder is a polar control retarder that is arranged, in a switchable state of the switchable liquid crystal retarder, simultaneously to introduce no net relative phase shift to orthogonal polarisation components of light passed by the display polariser along an axis along a normal to the plane of the switchable liquid crystal retarder and introducing a relative phase shift to orthogonal polarisation components of light passed by the display polariser along an axis inclined to a normal to the plane of the switchable liquid crystal retarder;
- switchable retarder control electrodes arranged to apply a voltage for controlling the state of the switchable liquid crystal retarder;
- at least one touch electrode array arranged in a layer on the output side of the switchable retarder control electrodes;
- and
- at least one passive retarder arranged between the switchable liquid crystal retarder and the additional polariser, wherein the at least one passive retarder comprises a pair of passive uniaxial retarders having optical axes in the plane of the passive uniaxial retarders that are crossed, and wherein the at least one touch electrode array comprises a pair of touch electrode arrays formed on outer surfaces of respective ones of the pair of passive uniaxial retarders, and said at least one dielectric layer comprises the pair of passive uniaxial retarders.
5 more elements
A touch input display device comprising:
- a spatial light modulator (SLM) arranged to output light;
- a display polariser arranged on the output side of the SLM, wherein the display polariser is a linear polariser;
- an additional polariser arranged on the output side of the display polariser wherein the additional polariser is a linear polariser;
- a switchable liquid crystal retarder comprising a layer of liquid crystal material arranged between the display polariser and the additional polariser, wherein the switchable liquid crystal retarder is a polar control retarder that is arranged, in a switchable state of the switchable liquid crystal retarder, simultaneously to introduce no net relative phase shift to orthogonal polarisation components of light passed by the display polariser along an axis along a normal to the plane of the switchable liquid crystal retarder and introducing a relative phase shift to orthogonal polarisation components of light passed by the display polariser along an axis inclined to a normal to the plane of the switchable liquid crystal retarder;
- switchable retarder control electrodes arranged to apply a voltage for controlling the state of the switchable liquid crystal retarder;
- at least one touch electrode array arranged in a layer on the output side of the switchable retarder control electrodes;
- and
- a control system, wherein the control system is arranged to apply a drive voltage to the switchable retarder control electrodes for controlling the switchable liquid crystal retarder, and the control system is arranged to address the at least one touch electrode array for capacitive touch sensing, and wherein the drive voltage has a waveform having a root mean square value that provides a constant liquid crystal optical alignment state of the liquid crystal retarder and having arithmetic average of zero.
5 more elements
A touch input display device comprising:
- a spatial light modulator (SLM) arranged to output light;
- a display polariser arranged on the output side of the SLM, wherein the display polariser is a linear polariser;
- an additional polariser arranged on the output side of the display polariser wherein the additional polariser is a linear polariser;
- a switchable liquid crystal retarder comprising a layer of liquid crystal material arranged between the display polariser and the additional polariser, wherein the switchable liquid crystal retarder is a polar control retarder that is arranged, in a switchable state of the switchable liquid crystal retarder, simultaneously to introduce no net relative phase shift to orthogonal polarisation components of light passed by the display polariser along an axis along a normal to the plane of the switchable liquid crystal retarder and introducing a relative phase shift to orthogonal polarisation components of light passed by the display polariser along an axis inclined to a normal to the plane of the switchable liquid crystal retarder;
- switchable retarder control electrodes arranged to apply a voltage for controlling the state of the switchable liquid crystal retarder;
- at least one touch electrode array arranged in a layer on the output side of the switchable retarder control electrodes;
- and
- a control system, wherein the control system is arranged to apply a drive voltage to the switchable retarder control electrodes for controlling the switchable liquid crystal retarder, and the control system is arranged to address the at least one touch electrode array for capacitive touch sensing, and wherein the control system is further arranged to address the SLM, and wherein the drive voltage that the control system is arranged to apply to the switchable retarder control electrodes is synchronised with respect to the addressing of the SLM.
5 more elements
A touch input display device comprising:
- a spatial light modulator (SLM) arranged to output light a display polariser arranged on the output side of the SLM, wherein the display polariser is a linear polariser;
- an additional polariser arranged on the output side of the display polariser wherein the additional polariser is a linear polariser;
- a switchable liquid crystal retarder comprising a layer of liquid crystal material arranged between the display polariser and the additional polariser, wherein the switchable liquid crystal retarder is a polar control retarder that is arranged, in a switchable state of the switchable liquid crystal retarder, simultaneously to introduce no net relative phase shift to orthogonal polarisation components of light passed by the display polariser along an axis along a normal to the plane of the switchable liquid crystal retarder and introducing a relative phase shift to orthogonal polarisation components of light passed by the display polariser along an axis inclined to a normal to the plane of the switchable liquid crystal retarder;
- switchable retarder control electrodes arranged to apply a voltage for controlling the state of the switchable liquid crystal retarder;
- at least one touch electrode array arranged in a layer on the output side of the switchable retarder control electrodes;
- and
- a control system, wherein the control system is arranged to apply a drive voltage to the switchable retarder control electrodes for controlling the switchable liquid crystal retarder, and the control system is arranged to address the at least one touch electrode array for capacitive touch sensing, and wherein the control system is further arranged to address the SLM, and wherein the control system is arranged to address the SLM using an addressing scheme including a vertical blanking interval, and the control system being arranged to address the at least one touch electrode array during the vertical blanking interval.
4 more elements
A method of controlling a touch input display device comprising:
- a spatial light modulator (SLM) arranged to output light;
- a display polariser arranged on the output side of the SLM, wherein the display polariser is a linear polariser;
- an additional polariser arranged on the output side of the display polariser wherein the additional polariser is a linear polariser;
- a switchable liquid crystal retarder comprising a layer of liquid crystal material arranged between the display polariser and the additional polariser;
- at least one passive retarder arranged between the switchable liquid crystal retarder and the additional polariser;
- switchable retarder control electrodes arranged to apply a voltage for controlling the switchable liquid crystal retarder;
- and
- at least one touch electrode array arranged in a layer on the output side of the switchable retarder control electrodes,
- wherein the method comprises:
- applying a drive voltage to the switchable retarder control electrodes for controlling the switchable liquid crystal retarder, wherein the drive voltage has a waveform including periods where the drive voltage is constant;
- and
- addressing the at least one touch electrode array for capacitive touch sensing during at least one of the periods where the drive voltage is constant.
9 more elements
Dependencies are inferred from the claim text.