REFLECTIVE AND TRANSFLECTIVE OPERATION MODES FOR A DISPLAY DEVICE

• US 20130082607A1
• Filed: 03/11/2011
• Published: 04/04/2013
• Est. Priority Date: 03/11/2010
• Status: Active Grant

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Pixtronix, Incorporated (Qualcomm, Inc.)
• Inventors: Gandhi, Jignesh, Hagood, Nesbitt W. IV, Kim, Je Hong, Halfman, Mark Douglas
• Granted Patent: US 9,398,666 B2
• Time in Patent Office: Days
• US Class Current: 315/153
• CPC Class Codes: G09G 2300/0456 with a reflective area and a transmissive area combined in one pixel, such as in transflectance pixels
• CPC Class Codes: G09G 2300/08 Active matrix structure, i.e. with use of active elements, inclusive of non-linear two terminal elements, in the pixels together with light emitting or modulating elements
• CPC Class Codes: G09G 2310/0235 Field-sequential colour display
• CPC Class Codes: G09G 2330/021 Power management, e.g. power saving
• CPC Class Codes: G09G 2360/144 the light being ambient light
• CPC Class Codes: G09G 2360/16 Calculation or use of calculated indices related to luminance levels in display data
• CPC Class Codes: G09G 2370/04 Exchange of auxiliary data, i.e. other than image data, between monitor and graphics controller
• CPC Class Codes: G09G 3/2022 using sub-frames
• CPC Class Codes: G09G 3/3413 Details of control of colour illumination sources
• CPC Class Codes: G09G 3/3433 using light modulating elements actuated by an electric field and being other than liquid crystal devices and electrochromic devices using liquid crystal devices G09G3/36; using electrochromic devices G09G3/38
• CPC Class Codes: H05B 47/165 following a pre-assigned programmed sequence; Logic control [LC]
• CPC Class Codes: H05B 47/17 Operational modes, e.g. switching from manual to automatic mode or prohibiting specific operations

Abstract

A direct-view display apparatus includes a transparent substrate, an internal light source, a plurality of light modulators coupled to the transparent substrate, and a controller for controlling the states of the plurality of light modulators and the internal light source. The controller is configured to cause the display to transition from one of a transmissive, reflective and transflective mode, to a second of said modes.

Claims

1-63. -63. (canceled)

64. A direct-view display apparatus, comprising:

a transparent substrate;

an internal light source;

a plurality of light modulators coupled to the transparent substrate; and

a controller for controlling the states of the plurality of light modulators and the internal light source, wherein the controller is configured to cause the display to;

display at least one image in a transmissive mode of operation by illuminating the internal light source at a first intensity and outputting data signals indicative of desired states of the plurality of light modulators through a first set of data voltage interconnects coupled to the plurality of light modulators such that the plurality of light modulators modulate light emitted by the internal light source;

detect a first signal instructing the display apparatus to transition to a transflective mode of operation;

transition, in response to the first signal, to the transflective mode of operation, wherein transitioning to the transflective mode includes decreasing the first intensity of the internal light source to a second intensity; and

display at least one image in the transflective mode of operation by outputting data signals indicative of desired states of the plurality of light modulators through the same first set of data voltage interconnects to the plurality of light modulators to modulate light originating from the ambient and the internal light source.

65. The apparatus of claim 64, comprising:

detecting a second signal instructing the display apparatus to transition to a reflective mode of operation;

transitioning, in response to the second signal, to the reflective mode of operation; and

displaying at least one image in the reflective mode of operation by, while keeping the internal light source un-illuminated, outputting data signals indicative of desired states of the plurality of light modulators through the same first set of data voltage interconnects to the plurality of light modulators to modulate light originating from the ambient.

66. The apparatus of claim 64, wherein in the transmissive mode, the plurality of light modulators modulate light emitted by the internal light source and light originating from the ambient.

67. The apparatus of claim 65, wherein the controller controls at least one light modulator to operate in both the transmissive mode and the reflective mode.

68. The apparatus of claim 64, wherein transitioning to the transflective mode reduces power consumption by the display apparatus.

69. The apparatus of claim 64, wherein the controller is further configured to transition to an operating mode in which images are displayed with more colors than another operating mode of the display device.

70. The apparatus of claim 64, wherein the controller derives the signal from at least one of information to be displayed by the display apparatus and an amount of energy stored in a battery.

71. The apparatus of claim 64, wherein decreasing the first intensity of the light source during transition to the transflective mode of operation includes decreasing the first intensity such that at least about 30% of the light modulated by the light modulators originates from the ambient.

72. The apparatus of claim 64, wherein the first signal is based at least in part on detected ambient light.

73. The apparatus of claim 65, wherein the controller is configured to transition to the reflective mode in response to a signal based on the detected ambient light.

74. The apparatus of claim 72, wherein displaying at least one image in the transmissive mode includes modulating light in accordance with a first number of grayscale divisions for the image, and wherein displaying at least one image in the transflective or reflective modes includes modulating light in accordance with a second number of grayscale divisions, wherein the second number of grayscale divisions is less than the first number of grayscale divisions.

75. The apparatus of claim 65, wherein displaying at least one image in the reflective mode includes at least one of modulating the image as a black and white image, and modulating light with at least 3 grayscale divisions.

76. The apparatus of claim 64, wherein displaying at least one image in the transflective mode includes at least one of modulating the image as a black and white image, and modulating light with at least 3 grayscale divisions.

77. The apparatus of claim 64, wherein displaying at least one image in the transflective mode includes modulating light to form a color image, and wherein the image is modulated with only 1 grayscale division per color.

78. The apparatus of claim 64, wherein displaying at least one image in the transflective mode includes modulating light to form a color image, and wherein the image is modulated with at least 2 grayscale divisions per color.

79. The apparatus of claim 72, wherein the internal light source includes at least first and second light sources corresponding to different colors, and wherein the controller measures at least one color component of the detected ambient light, and adjusts the first intensity of at least one of the first and second light sources based on the measurement of the at least one color component of the detected ambient light.

80. The apparatus of claim 65, wherein displaying at least one image in the transmissive mode includes modulating the light according to a first frame rate.

81. The apparatus of claim 80, wherein displaying at least one image in the transflective or reflective modes includes modulating light in accordance with a second frame rate, wherein the second frame rate that is less than the first frame rate.

82. The apparatus of claim 65, wherein transitioning to the reflective mode of operation includes loading, from a memory, operating parameters corresponding to the reflective mode.

83. The apparatus of claim 65, wherein displaying at least one image in the reflective mode includes converting a color image into a black and white image for display.

84. The apparatus of claim 65, wherein displaying at least one image in the transmissive mode includes modulating the plurality of light modulators according to a first sequence of timing signals which control the loading of image data to the plurality of light modulators.

85. The apparatus of claim 84, wherein displaying at least one image in the transflective or reflective modes includes modulating the plurality of light modulators according to the same first sequence of timing signals which control the loading of image data to the plurality of light modulators.

86. The apparatus of claim 84, wherein displaying at least one image in the transflective or reflective modes includes modulating the plurality of light modulators according to a second sequence of timing signals that is different from the first sequence.

87. The apparatus of claim 86, wherein displaying at least one image in the transflective or reflective modes includes loading a subset of image data to the plurality of light modulators.

88. The apparatus of claim 64, wherein the light emitted by the internal light source passes through a plane defined by the plurality of light modulators.

89. The apparatus of claim 64, wherein the light modulators are MEMS-based shutters.

90. A method for controlling a display apparatus, comprising:

displaying, by the display apparatus, at least one image in a transmissive mode of operation by illuminating an internal light source at a first intensity and outputting data signals indicative of desired states of a plurality of light modulators such that the plurality of light modulators modulate light emitted by the internal light source;

detecting a first signal instructing the display apparatus to transition to a transflective mode of operation;

in response to the first signal, decreasing the first intensity of the internal light source to a second intensity; and

displaying, by the display apparatus, at least one image in the transflective mode of operation by illuminating the internal light source at a second intensity and outputting data signals indicative of desired states of the plurality of light modulators such that the plurality of light modulators modulate light originating from the ambient and the internal light source.

91. The method of claim 90, further comprising:

detecting a second signal instructing the display apparatus to transition to a reflective mode of operation;

transitioning by the display apparatus, in response to said signal, to the reflective mode of operation; and

displaying at least one image by, while keeping the internal light source un-illuminated, outputting data signals indicative of desired states of the plurality of light modulators through the same first set of data voltage interconnects to the plurality of light modulators to modulate light originating from the ambient.

92. A display apparatus, comprising:

at least one internal light source;

at least one reflective optical cavity, having a first reflective layer and a second reflective layer opposing the first reflective layer, for receiving ambient light and light emitted from the at least one internal light source;

a plurality of light modulators for modulating light leaving the reflective optical cavity towards a viewer; and

a controller configured to;

display at least one image by illuminating the internal light source at a first intensity and outputting data signals indicative of desired states of the plurality of light modulators such that the plurality of light modulators modulate light emitted by the internal light source;

detect a first signal;

in response to the signal, decrease the first intensity of the internal light source to a second intensity; and

display at least one image by illuminating the light source at the second intensity and outputting data signals indicative of desired states of the plurality of light modulators to the plurality of light modulators to modulate light.

93. The apparatus of claim 92, wherein the second intensity is zero.

94. The apparatus of claim 92, further comprising a plurality of data interconnects coupled to the plurality of light modulators and the controller, wherein the data interconnects are used to output data signals indicative of desired states of the plurality of light modulators.

95. The apparatus of claim 92, wherein the plurality of light modulators modulate both light emitted by the internal light source and light originating from the ambient.

96. The apparatus of claim 92, wherein at least about 30% of the light modulated by the light modulators originates from the ambient, and the controller outputs signals to control the plurality of light modulators to modulate both ambient light, and light emitted by the at least one internal light source.

97. The apparatus of claim 92, wherein the light emitted by the at least one internal light source is at a lesser intensity than the first intensity, thereby increasing the percentage of ambient light output.

100. The apparatus of claim 92, wherein the first reflective layer includes a rear-facing reflective layer and the second reflective layer includes a front facing reflective layer.

101. The apparatus of claim 92, wherein the controller is further configured to transition to an operating mode in which images are displayed with more colors than another operating mode of the display device.

102. The apparatus of claim 92, wherein the controller derives the signal from at least one of information to be displayed by the display apparatus, and an amount of energy stored in a battery.

118. The apparatus of claim 92, wherein the light emitted by the internal light source passes through a plane defined by the plurality of light modulators.

119. The apparatus of claim 92, wherein the light modulators are MEMS-based shutters.

98. The apparatus of claim 98, further comprising a sensor for detecting and measuring ambient light.

99. The apparatus of claim 98, wherein the controller decreases the intensity of the light emitted by the at least one internal light source based on at least one color component in the detected ambient light.

103. The apparatus of claim 98 wherein the controller is configured to transition to one of a transmissive mode, a reflective mode and a transflective mode in response to a signal based on the detected ambient light.

104. The apparatus of claim 103, wherein displaying at least one image in the transmissive mode includes modulating light in accordance with a first number of grayscale divisions for the image, and wherein displaying at least one image in the transflective or reflective modes includes modulating light in accordance with a second number of grayscale divisions, wherein the second number of grayscale divisions is less than the first number of grayscale divisions.

105. The apparatus of claim 103, wherein displaying at least one image in the reflective mode includes at least one of modulating the image as a black and white image, and modulating light with at least 3 grayscale divisions.

106. The apparatus of claim 103, wherein displaying at least one image in the transflective mode includes at least one of modulating the image as a black and white image, and modulating light with at least 3 grayscale divisions.

107. The apparatus of claim 103, wherein displaying at least one image in the transflective mode includes modulating light to form a color image, and wherein the image is modulated with only 1 grayscale division per color.

108. The apparatus of claim 103, wherein displaying at least one image in the transflective mode includes modulating light to form a color image, and wherein the image is modulated with at least 2 grayscale divisions per color.

109. The apparatus of claim 98, wherein the internal light source includes at least first and second light sources corresponding to different colors, and wherein the controller measures at least one color component of the detected ambient light, and adjusts the intensity of at least one of the first and second light sources based on the measurement of the at least one color component of the detected ambient light.

110. The apparatus of claim 108, wherein displaying at least one image in the transmissive mode includes modulating the light according to a first frame rate.

111. The apparatus of claim 110, wherein displaying at least one image in the transflective or reflective modes includes modulating light in accordance with a second frame rate, wherein the second frame rate that is less than the first frame rate.

112. The apparatus of claim 103, wherein transitioning to the reflective mode of operation includes loading, from a memory, operating parameters corresponding to the reflective mode.

113. The apparatus of claim 103, wherein displaying at least one image in the reflective mode includes converting a color image into a black and white image for display.

114. The apparatus of claim 103, wherein displaying at least one image in the transmissive mode includes modulating the plurality of light modulators according to a first sequence of timing signals which control the loading of image data to the plurality of light modulators.

115. The apparatus of claim 114, wherein displaying at least one image in the transflective or reflective modes includes modulating the plurality of light modulators according to the same first sequence of timing signals which control the loading of image data to the plurality of light modulators.

116. The apparatus of claim 114, wherein displaying at least one image in the transflective or reflective modes includes modulating the plurality of light modulators according to a second sequence of timing signals that is different from the first sequence.

117. The apparatus of claim 116, wherein displaying at least one image in the transflective or reflective modes includes loading a subset of image data to the plurality of light modulators.

120. The apparatus of claim 103, wherein the controller controls at least one light modulator to operate in both the transmissive mode and the reflective mode.

121. A method for controlling a display apparatus, comprising:

displaying, by the display apparatus, at least one image by illuminating an internal light source at a first intensity and outputting data signals indicative of desired states of a plurality of light modulators such that the plurality of light modulators modulate light emitted by the internal light source;

detecting a signal; and

in response to said signal,

displaying, by the display apparatus, at least one image by illuminating the internal light source at a second intensity and outputting data signals indicative of desired states of the plurality of light modulators.

122. The method of claim 121, wherein the second intensity is zero.