A scanning projector includes a brightness compensation component. The brightness compensation component modifies pixel brightness as a function of instantaneous scan phase of a sinusoidally scanning mirror. The brightness compensation component uses different brightness compensation functions based on whether the instantaneous scan phase is above or below a threshold. The threshold may correspond to a knee of a maximum laser power limit curve.

FIELD

The present invention relates generally to projection systems, and more specifically to scanning projection systems.

BACKGROUND

Scanning laser projectors typically scan a modulated laser beam in a raster pattern to display an image. Due to many possible factors, the resulting laser beam spot may traverse the raster pattern at a varying rate. For example, a sinusoidally scanned laser beam will produce a laser spot that traverses the raster pattern fastest near the center and slowest away from the center. The varying rate of laser spot traversal may result in brightness variations in the displayed image.

DETAILED DESCRIPTION

FIG. 1shows a scanning laser projector in accordance with various embodiments of the present invention. Scanning laser projector100includes image processing component with brightness compensation102, light source(s)112, micro-electronic machine (MEMS) device160having scanning mirror162, mirror drive circuits116, and clock generation component140. Scanning laser projector100also includes guiding optics134and136.

In operation, image processing component with brightness compensation102receives video data on node101and produces compensated pixel data on node111used to drive light source(s)112when pixels are to be displayed. The video data on node101represents image source data that is typically received with pixel data on a rectilinear grid, but this is not essential. For example, video data on node101may represent a grid of pixels at any resolution (e.g., 640×480, 848×480, 1920×1080). Scanning laser projector100is a scanning projector that scans a raster pattern shown at180. The raster pattern does not necessarily align with the rectilinear grid in the image source data, and image processing component102operates to produce display pixel data that will be displayed at appropriate points on the raster pattern. For example, in some embodiments, image processing component102interpolates vertically and/or horizontally between pixels in the source image data to determine display pixel values along the scan trajectory of the raster pattern.

Light source(s)112receive the compensated pixel data output from image processing component102, and produce light having grayscale values in response thereto. Light source(s)112may be monochrome or may include multiple different color light sources. For example, in some embodiments, light source(s)112includes red, green, and blue light sources. In these embodiments, image processing component102outputs compensated pixel data corresponding to each of the red, green, and blue light sources.

In some embodiments, light source(s)112may include one or more laser light producing devices. For example, in some embodiments, the light source(s)112may include laser diodes. In these embodiments, light source(s)112may also include driver circuits that accept and/or condition drive signals. For example, driver circuits may include digital-to-analog (D/A) converters, transimpedance amplifiers, coupling circuits, bias circuits, switches, and the like. Light beam(s) from light source(s)112are directed to mirror162via guiding optics134,136. Any type of optical element may be included in the light path between light source(s)112and mirror162. For example, scanning laser projector100may include collimating lenses, dichroic mirrors, or any other suitable optical elements.

Scanning mirror162is positioned to receive the light beam(s) from light source(s)112. In some embodiments, scanning mirror162is a sinusoidally scanning mirror that scans sinusoidally on at least one axis. Further, in some embodiments, scanning mirror162scans back and forth and has an instantaneous scan phase that sweeps through a zero phase value and positive and negative video extents phase values.

Scanning mirror162deflects on two axes in response to electrical stimuli received on node193from mirror drive circuits116. While moving on the two axes, scanning mirror162reflects light provided by light source(s)112. The reflected light sweeps a raster pattern and paints individual pixels as the light beams are modulated, resulting in an image display at180. The shape of the raster pattern swept by scanning mirror162is a function of the mirror movement on its two axes. For example, in some embodiments, scanning mirror162sweeps in a first dimension (e.g., horizontal dimension) according to a sinusoidal stimulus, resulting in a substantially sinusoidal horizontal sweep. Also for example, in some embodiments, scanning mirror162sweeps in a second dimension (e.g., vertical dimension) in response to sawtooth wave stimulus, resulting in a substantially linear and unidirectional vertical sweep.

MEMS device160is an example of a scanning mirror assembly that scans light in two dimensions. In some embodiments the scanning mirror assembly includes a single mirror that scans in two dimensions (e.g., on two axes). Alternatively, in some embodiments, MEMS device160may be an assembly that includes two scan mirrors, one which deflects the beam along one axis, and another which deflects the beam along a second axis largely perpendicular to the first axis.

MEMS device160produces a sync signal on node161. The sync signal on node161provides information regarding mirror position. For example, in some embodiments, the sync signal is a horizontal sync signal that transitions a known number of times per horizontal sweep of scanning mirror162, and in other embodiments, the sync signal is a vertical sync signal that transitions a known number of times per vertical sweep of scanning mirror162. In some embodiments, MEMS device160includes sensors and/or circuits to generate the sync signal. For example, in some embodiments, MEMS device160includes one or more piezoelectric sensors that sense the position of scanning mirror162. Also for example, in some embodiments, MEMS device160also includes one or more comparators, delay lines, or other circuits to generate the sync signal from sensor signals.

Clock generation component140receives the sync signal on node161and generates a clock signal on node141. Clock generation component140may include any circuits capable of generating a clock signal from a sync signal. For example, in some embodiments, clock generation component140includes a phase lock loop circuit having a phase comparator, voltage controlled oscillator, frequency multipliers and/or dividers, and the like. In some embodiments, the clock signal on node141is a pixel clock that is used to time pixel data generation and display of pixels in the image displayed at180.

Image processing component102also includes a brightness compensation component configured to modify brightness of the light beam produced by light source(s)112. The brightness compensation component makes use of the compensation coefficients on node103, the sync signal on node161, and the clock signal on node141to determine when and how to modify pixel brightness. In some embodiments, the brightness compensation component uses at least two functions of the instantaneous scan phase, where a first function is used when the instantaneous scan phase is equal to the zero phase value at the horizontal center of raster pattern180, and a second function is used when an absolute value of the instantaneous scan phase is equal to the positive video extents phase value. These brightness compensation embodiments and others are described further below.

FIG. 2shows a raster pattern with brightness variations in accordance with various embodiments of the present invention. Raster pattern180is also shown in, and described with reference to,FIG. 1. Although raster pattern180shows only a few horizontal sweeps for each vertical sweep, this is not a limitation of the present invention. For example, in some embodiments, hundreds or thousands of horizontal sweeps occur for each vertical sweep.

FIG. 2shows the horizontal direction as the “first dimension,” and the vertical direction as the “second dimension.” This is for naming convention purposes only, and a 90 degree rotation can result in the first dimension being the vertical direction and the second dimension being the horizontal direction.

FIG. 2also shows negative video extent202and positive video extent204in the fast scan direction. Video extents202,204represent the extent of the raster pattern that is used to display video. Pixels are displayed between the extents but not outside the extents. If the horizontal (fast scan) center is considered to be zero phase, scanning mirror162(FIG. 1) scans through the zero phase position, the negative video extent position202, and the positive video extent position204.

In a scanned beam projection system (100,FIG. 1) with a resonant mirror drive for the fast axis, the scanning mirror motion is inherently fastest at the center of the fast scan extents (zero phase position) and the scanning mirror slows down towards the edges of the image field of view. As the scanning mirror slows down towards the edges, the pixel period duration increases. If the light sources are driven to a fixed power level for all pixel locations, the pixels appear brighter at the edges of the field of view and dimmer towards the center.

This phenomenon is represented by the perceived brightness curve at210. Perceived brightness210represents the increased brightness near the left and right edges of the raster pattern that results if the light sources are driven with a fixed power level for all pixel locations. Because the mirror velocity can be approximated by a cosine curve, perceived brightness210is also represented by a cosine curve having increased brightness near the video extents as a result of sinusoidal scanning in the first dimension.

In some embodiments, a brightness compensation shown at220is applied to the pixel data to compensate for the perceived brightness shown at210. Brightness compensation220modifies or adjusts the brightness of individual pixels based on horizontal distance from a center of the image. For example, for a brightness compensation normalized to a value of one, the brightness of individual pixels is not modified or adjusted at the horizontal center of the image. For the same brightness compensation normalized to a value of one, the brightness of individual pixels is reduced as the distance increases from the horizontal center of the image.

FIG. 2also shows brightness compensation230. Brightness compensation230is an example of a multi-segment brightness compensation function. Multi-segment brightness compensation may be useful for many purposes. In some embodiments, as the combined output laser power is increased, total instantaneous output power must still remain below a certain laser power limit in order to satisfy a certain laser classification. Examples of some laser classifications are described further below. Some embodiments of the present invention provide multi-segment brightness compensation that uses a plurality of different brightness compensation functions in order to increase overall image brightness while remaining within the same laser class. A first brightness compensation function may be used for horizontal distances associated with an instantaneous scan phase below a threshold, and a second brightness compensation function may used for horizontal distances associated with instantaneous phase values above the threshold.

Although multi-segment brightness compensation is useful for satisfying laser classifications as described above, in some embodiments, multi-segment brightness compensation is used for other purposes. For example, brightness variations may stem from projection geometry as well as the varying mirror scan speed. If a projection surface is irregular, or if the projector is not nominally orthogonal to the projection surface, multi-segment brightness variations may result. In these embodiments, multi-segment brightness compensation may be used to modify pixel brightness to effect any desired relationship between uncompensated pixel data and compensated pixel data.

FIG. 3shows an image processing component with brightness compensation in accordance with various embodiments of the present invention. Image processing component102includes video buffer320, interpolator330, scan phase determination component310, and brightness compensation component340. The clock signal on node141is shown with one arrow to signify that it is provided to any functional block that uses it. For example, in some embodiments, the clock signal is provided to all other functional blocks depicted inFIG. 3.

Scan phase determination component310receives a sync signal on node161and outputs an instantaneous scan phase value θ that represents the instantaneous scan phase of the scanning mirror. The sync signal may be any signal or signals that allows the instantaneous scan phase value to be determined. For example, in some embodiments, the sync signal is a vertical sync signal, and in other embodiments, the sync signal is a horizontal sync signal. Scan phase determination component310may determine the instantaneous scan phase in any suitable manner. For example, in some embodiments, scan phase determination component310implements a modulo it counter that adds a fixed phase value for every clock period.

Video buffer320receives video data on node101. As described above, the video data may be in any format, including at any color depth and resolution. Buffer320stores multiple entries corresponding to multiple pixels. In some embodiments, buffer320stores one horizontal line worth of pixels, and in other embodiments, buffer320stores multiple horizontal lines worth of pixels. In still further embodiments, buffer320stores a complete frame of pixels, or multiple frames of pixels.

Buffer320may be implemented using any suitable hardware structure. For example, in some embodiments, buffer320is implemented with a dual-port random access memory, and in other embodiments, buffer320is implement with a first-in-first-out (FIFO) storage device.

Interpolator330receives pixel data from buffer320, and performs interpolation to determine display pixel values that correspond to the instantaneous scan phase value of the scanning mirror. In some embodiments, interpolator330interpolates only between pixels on a single horizontal or vertical line (one dimensional interpolation), an in other embodiments, interpolator330interpolates between pixels on the same horizontal line as well as between pixels on different horizontal lines (two dimensional interpolation).

Interpolator330may be implemented using any suitable hardware structure. For example, in some embodiments, interpolator330is implemented with registers, adders, shifters, and multipliers. Interpolator330may also include embedded control components such as finite state machines to control the various computational elements used to perform the interpolation between pixels in buffer320.

The interpolated pixel data is provided to brightness compensation component340. Brightness compensation component340modifies the output brightness of pixels as a function of the instantaneous scan phase value θ. As described above, the mirror velocity can be approximated by a cosine curve and following from that a brightness compensation factor may be defined as:
brightness_compensation=BF+((1−BF)*cos(θ)),

where BF is a brightness factor that takes on a value between 0 and 1 (1=no brightness compensation). For a pixel at θ, the output pixel laser power is computed as:
compensated pixel data=pixel data*brightness_compensation.

In other embodiments, the brightness compensation follows a multi-segment approach. For example, the brightness compensation may be determined using a first function when the absolute value of θ is below a threshold, and may be determined using a second function when the absolute value of θ is above the threshold. In these embodiments, the brightness compensation factor may be defined as:

where CC1, CC2, CC3, and CC4 are compensation coefficients, and “knee” is a threshold. Various multi-segment embodiments include more than one threshold and more than two functions of θ to determine brightness compensation factors. Any number of thresholds and brightness compensation functions may be included without departing from the scope of the present invention.

In some embodiments, the compensation coefficients are static values that are set once and do not change. In other embodiments, the compensation coefficients may be modifiable during operation of the scanning laser projection. For example, the compensation coefficients may be held in registers that are modifiable by a control component (not shown) such as a microprocessor or finite state machine. The compensation coefficients may be modified when a user interacts with the laser projector (e.g., when a user modifies a brightness setting), or they may be modified using an algorithm within a control component in the absence of user interaction.

As described further below, some embodiments employ multi-segment brightness compensation to increase output lumens of a scanning laser projector while remaining within the same laser class. Further, other embodiments employ multi-segment brightness compensation to make other value-added trade offs in display quality, such as brightness uniformity versus average output power. And still further embodiments employ multi-segment brightness compensation to compensate for brightness variations due to projection geometry.

FIG. 4shows a brightness compensation component in accordance with various embodiments of the present invention. Brightness compensation component340includes multipliers410,414,420,424, and470, adders412,416,422, and426, cosine determination component402, absolute value determination component440, comparator450, and multiplexer460. The clock signal on node141is shown with one arrow to signify that it is provided to any functional block that uses it. For example, in some embodiments, the clock signal is provided to all other functional blocks depicted inFIG. 4.

The example circuit topology shown inFIG. 4performs multi-segment brightness compensation in accordance with the multi-segment example provide above with reference toFIG. 3. As shown inFIG. 4, the two functions include different coefficients applied to trigonometric functions of the instantaneous scan phase. The different coefficients are shown as (1−CC1) and (1−CC3), and the trigonometric functions are cosine functions. Also as shown inFIG. 4, the two functions include different offsets summed with trigonometric functions of the instantaneous scan phase. The different offsets are shown as (CC1*CC2) and (CC3*CC4), and the trigonometric functions are cosine functions.

Multiplier470is shown as a single multiplier that multiplies pixel data with the brightness compensation. In some embodiments, multiplier470includes more than one physical multiplier. For example, some embodiments include three multipliers, where each multiplier applies the brightness compensation factor to a different color pixel data (e.g., red, green and blue).

AlthoughFIG. 4shows multi-segment brightness compensation with a single threshold, this is not a limitation of the present invention. For example, some embodiments include multi-segment brightness compensation with more than one threshold.

FIGS. 5 and 6show plots of brightness compensation using a single compensation function.FIG. 5shows mirror velocity510, brightness compensation540, brightness uniformity530, and laser power mask520, all as a function of the instantaneous mirror scan phase value θ.FIG. 5also shows positive video extent204and negative video extent202. The active video extents in this example are out to approximately +/−1.2 radians (or 94% of scan range is reserved for active video). All curves shown inFIG. 5are normalized to a value of one for simplicity.

The laser power mask520represents a maximum desirable laser power as a function of instantaneous scan phase. Laser power mask520may be derived using any criteria, including but not limited to: laser class, projection geometry, projection surface discontinuities, and the like. For the sake of discussion, and to provide a concrete example, laser power mask520is in the shape of a Class 2 IEC 60825-1 laser power limits for a ˜26 lumen system.

Brightness compensation540is a single segment brightness function of the form:
brightness_compensation=BF+((1−BF)*cos(θ)),

Brightness530shows the brightness uniformity of the final image formed when the brightness compensation540is applied. When brightness compensation540is applied, peak brightness variation (variation of brightness uniformity530) equals 5.17%, and 13 point ANSI uniformity equals 97.34%. Brightness compensation540is outside (above) the limit bounds specified by the laser power mask520on both the left and right side of the scan extents. In general, this implies output laser power above the desirable limits as specified by mask520, and in this specific example, this implies a violation of Class 2 IEC limits.

FIG. 6also shows single segment brightness compensation. In contrast to the brightness compensation shown inFIG. 5, the brightness compensation640inFIG. 6remains below the laser power mask520, and therefore satisfies a particular laser class requirement.

Brightness compensation640is a single segment brightness function of the form:
brightness_compensation=BF+((1−BF)*cos(θ)),

Brightness630shows the brightness uniformity of the final image formed when the brightness compensation640is applied. When brightness compensation640is applied, peak brightness variation (variation of brightness uniformity630) equals 52.78%, and 13 point ANSI uniformity equals 71.13. Brightness compensation640results in a system that remains in a certain laser class, but overall brightness and brightness uniformity are reduced as compared to brightness compensation540(FIG. 5).

FIG. 7shows a plot of brightness compensation using more than one compensation function. Brightness compensation740provides multi-segment brightness compensation of the form:

where

CC4=0.654; and

Brightness compensation740increases total lumens output and also increases brightness uniformity by increasing the laser power drive while remaining under the laser power mask520. The example laser power mask520includes a knee, and brightness compensation740determines brightness compensation using a first function when the absolute value of the instantaneous mirror scan phase value θ is below the knee, and determines brightness compensation using a first function when the absolute value of the instantaneous mirror scan phase value θ is above the knee.

When brightness compensation640is applied, peak brightness variation (variation of brightness uniformity730) equals 52.57%, and 13 point ANSI uniformity equals 70.91. The multi-segment brightness compensation ofFIG. 7provides a gain of an additional ˜7% of output lumens over the single segment approach ofFIG. 6with nearly no loss of brightness uniformity.

In the example ofFIG. 7, brightness compensation740uses two functions of θ. The number of functions used can be limitless for increased granularity, but for simplicity only two are considered here.

FIG. 8shows a plot of brightness compensation using more than one compensation function at lower brightness levels. Brightness compensation840provides multi-segment brightness compensation of the form:

where

CC3=−0.409; and

The output lumens drop to about ˜15, peak brightness variation drops to 3.06%, and 13 point ANSI uniformity increases to 97.34%.

In some embodiments, the compensation coefficients are dynamically modified as the system brightness is varied between values represented byFIGS. 7 and 8. For example, the knee may be increased or decreased as the system brightness is varied. Also for example, CC1, CC2, CC3, and CC4 may be increased or decreased as the system brightness is varied.

FIG. 8represents an embodiment that increases brightness uniformity830in return for reduced total output lumens. Other embodiments may modify the compensation coefficients to make different tradeoffs between output lumens, brightness uniformity, and other factors.

As discussed above, laser power mask520may be derived using any criteria, including criteria related to IEC laser classes or classification. For example, in some embodiments, laser power or class limits might not be an issue depending on the product industrial design and the power levels to which the lasers are driven to in that application. However, what might be more applicable in these scenarios is a power limits mask that is derived from the geometry of the surface onto which the image is projected.

Consider a projection scenario in which laser projector100(FIG. 1) projects signage onto a surface that is convex with the projector nominally orthogonal to the center of the convex surface. In these embodiments, the projected content will fade to the sides from the center. In these embodiments, a laser power limit mask may be derived that allows for increasing brightness towards the edges while keeping brightness at the center nominally maximum. As the pixel period increases near the video extents, the perceived brightness towards the edge increases. In embodiments in which the projector is not nominally orthogonal to the projection surface, multiple scan phase thresholds may be employed to alter the perceived brightness distribution.

Consider another projection scenario, in which laser projector100(FIG. 1) projects onto a multi-segment projection surface. Segment1on the left and Segment3on the right are at the same distance from the projector and Segment2is in the center but further away from the projector than the other two segments. In these embodiments, a laser power limits mask may be derived so the brightness at the center is maximum, while pushing the brightness lower towards the edges, allowing for what appears to be a constantly bright image. In embodiments in which the segment thresholds are not equidistant from the center, the laser power limits mask may have multiple thresholds and not employ the absolute value block440inFIG. 4.

FIG. 9shows a flow diagram of methods in accordance with various embodiments of the present invention. In some embodiments, method900, or portions thereof, is performed by a scanning laser projector, embodiments of which are shown in previous figures. In other embodiments, method900is performed by a series of circuits or an electronic system. In some embodiments, method900compensates the brightness of individual pixels in a display image. Method900is not limited by the particular type of apparatus performing the method. Further, in some embodiments, some actions listed inFIG. 9are omitted from method900.

Method900is shown beginning with block910. As shown at910, an instantaneous scan phase of a sinusoidally scanning mirror that reflects a light beam is determined. In some embodiments, this may be performed by summing a fixed phase increment for each clock period, and synchronizing to a vertical or horizontal sync signal produced by the scanning mirror.

At920, the brightness of the light beam is adjusted using a first function of the instantaneous scan phase value if the absolute value of the instantaneous scan phase is below a threshold. In some embodiments, the threshold corresponds to a knee of a laser class' maximum laser power curve.

At930, the brightness of the light beam is adjusted using a second function of the instantaneous scan phase value if the absolute value of the instantaneous scan phase is above the threshold.

In some embodiments, the first and second functions differ by coefficients applied to a trigonometric function of the instantaneous scan phase value. In other embodiments, the first and second functions include different offsets summed with a trigonometric function of the instantaneous scan phase value.

FIG. 10shows a block diagram of a mobile device in accordance with various embodiments of the present invention. As shown inFIG. 10, mobile device1000includes wireless interface1010, processor1020, memory1030, and scanning projector1001. Scanning projector1001paints a raster image at180. Scanning projector1001is a scanning laser projector as described above with reference to previous figures. For example, scanning projector1001may include a brightness compensation component as describe above. The brightness compensation component may perform brightness compensation using one or more brightness functions, and may include multi-segment brightness compensation as described herein.

Scanning projector1001may receive image data from any image source. For example, in some embodiments, scanning projector1001includes memory that holds still images. In other embodiments, scanning projector1001includes memory that includes video images. In still further embodiments, scanning projector1001displays imagery received from external sources such as connectors, wireless interface1010, a wired interface, or the like.

Wireless interface1010may include any wireless transmission and/or reception capabilities. For example, in some embodiments, wireless interface1010includes a network interface card (NIC) capable of communicating over a wireless network. Also for example, in some embodiments, wireless interface1010may include cellular telephone capabilities. In still further embodiments, wireless interface1010may include a global positioning system (GPS) receiver. One skilled in the art will understand that wireless interface1010may include any type of wireless communications capability without departing from the scope of the present invention.

Processor1020may be any type of processor capable of communicating with the various components in mobile device1000. For example, processor1020may be an embedded processor available from application specific integrated circuit (ASIC) vendors, or may be a commercially available microprocessor. In some embodiments, processor1020provides image or video data to scanning projector1001. The image or video data may be retrieved from wireless interface1010or may be derived from data retrieved from wireless interface1010. For example, through processor1020, scanning projector1001may display images or video received directly from wireless interface1010. Also for example, processor1020may provide overlays to add to images and/or video received from wireless interface1010, or may alter stored imagery based on data received from wireless interface1010(e.g., modifying a map display in GPS embodiments in which wireless interface1010provides location coordinates).

FIG. 11shows a mobile device in accordance with various embodiments of the present invention. Mobile device1100may be a hand held projection device with or without communications ability. For example, in some embodiments, mobile device1100may be a handheld projector with little or no other capabilities. Also for example, in some embodiments, mobile device1100may be a device usable for communications, including for example, a cellular phone, a smart phone, a personal digital assistant (PDA), a global positioning system (GPS) receiver, or the like. Further, mobile device1100may be connected to a larger network via a wireless (e.g., WiMax) or cellular connection, or this device can accept data messages or video content via an unregulated spectrum (e.g., WiFi) connection.

Mobile device1100includes scanning projector1001to create an image with light at180. Mobile device1100also includes many other types of circuitry; however, they are intentionally omitted fromFIG. 11for clarity.

Mobile device1100includes display1110, keypad1120, audio port1102, control buttons1104, card slot1106, and audio/video (A/V) port1108. None of these elements are essential. For example, mobile device1100may only include scanning projector1001without any of display1110, keypad1120, audio port1102, control buttons1104, card slot1106, or A/V port1108. Some embodiments include a subset of these elements. For example, an accessory projector product may include scanning projector1001, control buttons1104and A/V port1108.

Display1110may be any type of display. For example, in some embodiments, display1110includes a liquid crystal display (LCD) screen. Display1110may always display the same content projected at180or different content. For example, an accessory projector product may always display the same content, whereas a mobile phone embodiment may project one type of content at180while displaying different content on display1110. Keypad1120may be a phone keypad or any other type of keypad.

A/V port1108accepts and/or transmits video and/or audio signals. For example, A/V port1108may be a digital port, such as a high definition multimedia interface (HDMI) interface, that accepts a cable suitable to carry digital audio and video data. Further, A/V port1108may include RCA jacks to accept composite inputs. Still further, A/V port1108may include a VGA connector to accept analog video signals. In some embodiments, mobile device1100may be tethered to an external signal source through A/V port1108, and mobile device1100may project content accepted through A/V port1108. In other embodiments, mobile device1100may be an originator of content, and A/V port1108is used to transmit content to a different device.

Audio port1102provides audio signals. For example, in some embodiments, mobile device1100is a media player that can store and play audio and video. In these embodiments, the video may be projected at180and the audio may be output at audio port1102. In other embodiments, mobile device1100may be an accessory projector that receives audio and video at A/V port1108. In these embodiments, mobile device1100may project the video content at180, and output the audio content at audio port1102.

Mobile device1100also includes card slot1106. In some embodiments, a memory card inserted in card slot1106may provide a source for audio to be output at audio port1102and/or video data to be projected at180. Card slot1106may receive any type of solid state memory device, including for example, Multimedia Memory Cards (MMCs), Memory Stick DUOS, secure digital (SD) memory cards, and Smart Media cards. The foregoing list is meant to be exemplary, and not exhaustive.

Control buttons1104may be used for any purpose. For example, in some embodiments, control buttons1104may be used to navigate a menu system on display1110.

FIG. 12shows a head-up display system in accordance with various embodiments of the invention. Projector1001is shown mounted in a vehicle dash to project the head-up display at1200. Although an automotive head-up display is shown inFIG. 12, this is not a limitation of the present invention. For example, various embodiments of the invention include head-up displays in avionics application, air traffic control applications, and other applications.

FIG. 13shows eyewear in accordance with various embodiments of the invention. Eyewear1300includes projector1001to project a display in the eyewear's field of view. In some embodiments, eyewear1300is see-through and in other embodiments, eyewear1300is opaque. For example, eyewear1300may be used in an augmented reality application in which a wearer can see the display from projector1001overlaid on the physical world. Also for example, eyewear1300may be used in a virtual reality application, in which a wearer's entire view is generated by projector1001. Although only one projector1001is shown inFIG. 13, this is not a limitation of the present invention. For example, in some embodiments, eyewear1300includes two projectors; one for each eye.

FIG. 14shows a gaming apparatus in accordance with various embodiments of the present invention. Gaming apparatus1400allows a user or users to observe and interact with a gaming environment. The game is navigated based on the motion, position or orientation of gaming apparatus1400, an apparatus that includes scanning laser projector1001. Other control interfaces, such as manually-operated buttons, foot pedals, or verbal commands, may also contribute to navigation around, or interaction with the gaming environment. For example, in some embodiments, trigger1442contributes to the illusion that the user or users are in a first person perspective video game environment, commonly known as a “first person shooter game.” Because the size and brightness of the projected display can be controlled by the gaming application in combination with the user's movement, gaming apparatus1400creates a highly believable or “immersive” environment for these users.

Many other first person perspective simulations can also be created by gaming apparatus1400, for such activities as 3D seismic geo-prospecting, spacewalk planning, jungle canopy exploration, automobile safety instruction, medical education, etc. Tactile interface1444may provide a variety of output signals, such as recoil, vibration, shake, rumble, etc. Tactile interface1444may also include a touch-sensitive input feature, such as a touch sensitive display screen or a display screen that requires a stylus. Additional tactile interfaces, for example, input and/or output features for a motion sensitive probe are also included in various embodiments of the present invention.

Gaming apparatus1400may also include audio output devices, such as integrated audio speakers, remote speakers, or headphones. These sorts of audio output devices may be connected to gaming apparatus1400with wires or through a wireless technology. For example, wireless headphones1446provide the user with sound effects via a Bluetooth connection, although any sort of similar wireless technology could be substituted freely. In some embodiments, wireless headphones1446may include microphone1445or binaural microphone1447, to allow multiple users, instructors, or observers to communicate. Binaural microphone1447typically includes microphones on each ear piece, to capture sounds modified by the user's head shadow. This feature may be used for binaural hearing and sound localization by other simulation participants.

Gaming apparatus1400may include any number of sensors1410that measure distance, ambient brightness, motion, position, orientation, and the like. For example, gaming apparatus1400may detect absolute heading with a digital compass, and detect relative motion with an x-y-z gyroscope or accelerometer. In some embodiments, gaming apparatus1400also includes a second accelerometer or gyroscope to detect the relative orientation of the device, or its rapid acceleration or deceleration. In other embodiments, gaming apparatus1400may include a Global Positioning Satellite (GPS) sensor, to detect absolute position as the user travels in terrestrial space.

Gaming apparatus1400may include battery1441and/or diagnostic lights1443. For example, battery1441may be a rechargeable battery, and diagnostic lights1443could indicate the current charge of the battery. In another example, battery1441may be a removable battery clip, and gaming apparatus1400may have an additional battery, electrical capacitor or super-capacitor to allow for continued operation of the apparatus while the discharged battery is replaced with a charged battery. In other embodiments, diagnostic lights1443can inform the user or a service technician about the status of the electronic components included within or connected to this device. For example, diagnostic lights1443may indicate the strength of a received wireless signal, or the presence or absence of a memory card. Diagnostic lights1443could also be replaced by any small screen, such as an organic light emitting diode or liquid crystal display screen. Such lights or screens could be on the exterior surface of gaming apparatus1400, or below the surface, if the shell for this apparatus is translucent or transparent.

Other components of gaming apparatus1400may be removable, detachable or separable from this device. For example, the scanning laser projector may be detachable or separable from gaming housing1449. In some embodiments, the subcomponents of the scanning laser projector may be detachable or separable from gaming housing1449, and still function.

Although the present invention has been described in conjunction with certain embodiments, it is to be understood that modifications and variations may be resorted to without departing from the scope of the invention as those skilled in the art readily understand. It is to be clearly understood that the above description is made only by way of example, and not as a limitation on the scope of the invention.