Image Projection Device

Abstract

A slide frame for use with an image projection device attachable to a mobile device having a camera flash is provided, the slide frame comprising: at least one slide transparency; and coded information associated with the at least one slide transparency, the coded information being readable by an application on the mobile device when the slide frame is attached to the image projection device to instruct the mobile device to provide at least one form of output selected from the group consisting of an audio output and a visual output.

Description

[Technical field]

[0001] The present disclosure relates generally to image projection devices, and more particularly to image projection devices that use a light source external to the device for illumination. [Background technology]

[0002] Image projection devices that utilize a light bulb to illuminate a slide transparency or film onto a screen in combination with a lens to magnify the image are well known. Slide projectors for viewing 35 mm slides became popular in the 1950s for home entertainment and educational use. These slide projectors included an incandescent light bulb or other light source, a collecting lens or reflector to direct the light onto the slide, a slide holder, and a focusing lens. Slide projectors fell out of use in favor of the more convenient digital media, which is projected onto a projection screen using a video projector or displayed on a large video monitor.

[0003] Flashlight projectors are novelties or toys that use a flashlight as a light source to illuminate a slide transparency. These devices generally include a mechanism to attach to the flashlight, a mechanism to hold the slide in place, and optics to focus and magnify the slide image. Examples include U.S. Patent Nos. 5,233,633, 5,233,633 and 5,233,633.

[0004] Mobile devices such as smartphones, digital cameras, and tablet computing devices may also be equipped with image projectors. This type of technology typically uses a liquid crystal on silicon display with a light source, such as a light emitting diode (LED), that illuminates the display. The addition of an image projector to a mobile device significantly increases the manufacturing cost of the mobile device. For example, US Pat. No. 6,399,433 discloses the use of a transmissive liquid crystal panel and an LED light source integrated into the mobile device. The LED light source illuminates a transmissive liquid crystal panel and an external projection lens that are removably attached to or integral with the mobile device to magnify and project the image from the transmissive liquid crystal panel onto a screen.

[0005] US Patent No. 5,999,333 discloses an entertainment accessory that can be coupled to a smartphone and place a projection element in the light path from the smartphone's LED. The entertainment device includes multiple projection elements of different colors or effects integrated into a rotary dial, allowing the user to create multiple different types of lighting projections and effects. The entertainment device can also change the lighting effects in response to sounds, such as music. The projection elements can be engraved or printed with graphic designs. Due to the integration of the graphics with the projection elements and the lack of coordination of the LED light source, this design does not allow for the projection of photo-quality images. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] U.S. Patent No. 2,445,651 [Patent Document 2] U.S. Patent No. 2,478,336 [Patent Document 3] U.S. Patent No. 5,321,449 [Patent Document 4] U.S. Patent No. 7,874,683 [Patent Document 5] U.S. Patent Application No. 2015 / 0323160 Summary of the Invention [Means for solving the problem]

[0007] According to a first aspect, there is provided an image projection device that can be used in conjunction with a mobile device having a camera flash. The image projection device includes a body defining an aperture, the body having a mounting mechanism for mounting to the mobile device to align the aperture with the camera flash, a slide frame receiving slot in the body transverse to the aperture, and a magnifying lens aligned with the aperture, the magnifying lens disposed at a front end of the body. A slide transparency housed in the slide frame is placed in the slide frame receiving slot, the camera flash illuminates the slide transparency, and the magnifying lens magnifies and projects the illuminated slide transparency onto a projection surface. The image projection device may also include a focus adjustment mechanism that houses the magnifying lens and allows axial translation of the magnifying lens relative to the aperture. The focus adjustment mechanism may include a telescopic mechanism or a screw-type mechanism.

[0008] The image projection device further includes a motor, electrically coupled to the mobile device for instructions. The motor is coupled to a focus adjustment mechanism such that the mobile device can instruct the motor to adjust the focus based on the projected image detected by the camera. Alternatively, or using an additional motor, the motor can be coupled to the slide frame using a gear mechanism and can receive instructions from the mobile device to advance the slide frame.

[0009] The image projection device may be attached to the mobile device using a removable adhesive, for example a nano-adhesive material. The attachment mechanism may be a clamp or a mobile device case, such as a mobile phone protective case.

[0010] The slide frame receiving slot of the image projection device can be configured to receive slide frames of any shape, including rectangular and circular slide frames, and can have flexible detents to interact with notches or indentations in the exterior surface of the slide frame to aid in alignment of the slide frame with the aperture.

[0011] The image projection device may also include a camera opening aligned with a camera of the mobile device to enable the camera of the mobile device to capture the coding block on the slide frame. The body may also include a light passage coupled to the aperture to allow light from a camera flash to enter the camera opening.

[0012] According to another aspect, a slide frame is provided that includes one or more slide transparencies and coded information associated with a corresponding slide transparency. The coded information is in a coding block adjacent to the slide transparency. The coding block encodes the information using a barcode, a color, and a near field communication tag. The coded information may also be encoded in an image of the slide transparency, such as by embedding a barcode in the slide image.

[0013] According to a third aspect, there is provided a method of operating an image projection apparatus and a mobile device, the method including identifying an alteration in the coded information detected by a slide interpreter, associating the alteration in the coded information with an event, and initiating the event. The event may be one or more of altering a video display of the mobile device, playing audio through a speaker of the mobile device, and operating a camera flash. The slide interpreter may be, for example, a camera or a near field communication sensor of the mobile device. [Brief description of the drawings]

[0014] For a better understanding of the various embodiments described herein, and to show more clearly how the same may be carried into effect, reference will now be made, by way of example only, to the accompanying drawings in which at least one illustrative embodiment is shown. [Figure 1] FIG. 2 is a rear view of a mobile device illustrating the camera aperture and camera flash. [Diagram 2] 2 is a rear view of an image projection device attached to the mobile device of FIG. 1. [Figure 2A] 3 is a cross-sectional view of the image projection device of FIG. 2 taken along line AA. [Figure 3A] FIG. 1 is a front exploded perspective view of an embodiment of an image projection device. [Figure 3B] FIG. 3B is a rear exploded perspective view of the image projection device of FIG. 3A. [Figure 4] FIG. 1 is a front view of a circular slide frame containing slide coding information in adjacent coding blocks. [Diagram 5] FIG. 2 is a front view of a rectangular slide frame containing slide encoding information embedded in a slide transparency. [Figure 6] FIG. 1 is a front view of a rectangular slide frame containing slide coding information in adjacent coding blocks. [Figure 7] FIG. 1 is a block diagram of a mobile device having a rear-facing camera and an associated rear camera flash. [Figure 8] FIG. 13 is a flow chart diagram of a method for triggering an event on a mobile device based on a change in an exposure slide. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] It will be appreciated that, for simplicity and clarity of illustration, where considered appropriate, numerous specific details have been set forth in order to provide a thorough understanding of the exemplary embodiments described herein. However, it will be understood by those skilled in the art that the embodiments described herein may be practiced without these specific details. In other instances, well-known methods, procedures and components have not been described in detail so as not to obscure the embodiments described herein. Moreover, this description should not be construed as limiting the scope of the embodiments described herein in any way, but rather serves merely to describe some of the possible ways in which they may be practiced.

[0016] 1, shown is a rear view of a generic mobile device 100 illustrating a camera flash 102 and a camera aperture 104 that may be used with embodiments of the image projection device described herein. Typically, the mobile device 100 includes a video display on a front side (not shown) of the mobile device 100 opposite a rear side 106. Some embodiments of the image projection device may be configured to work with a camera flash on the front facing side of the mobile device 100. Mobile devices 100 include handheld computing devices that include a camera flash 102 and may include smartphones, tablet computers, digital cameras, and potentially laptops.

[0017] The camera flash 102 is typically a light emitting diode flash and may be controlled by the mobile device 100 through a combination of software and hardware. The camera aperture 104 typically includes optics and a CMOS-based image sensor that captures digital images. The camera may likewise be controlled through a combination of software and hardware operating on the mobile device 100.

[0018] Embodiments of the image projection device may be configured to work with a mobile device 100 that uses a camera flash 102. The orientation of the camera flash 102 and the camera aperture 104 may vary depending on the manufacturer of the mobile device. For example, some mobile devices orient the camera flash 102 and the camera aperture 104 in a vertical or top-down orientation in the center of the back surface. Some embodiments of the image projection device described herein may be designed to mount to a specific device based on the dimensions and sensor orientation of the mobile device. Other embodiments may use other mounting mechanisms that are not dependent on the particular dimensions of the mobile device 100 or the orientation of the camera flash 102 or the camera aperture 104. In some embodiments, the image projection device described herein should not block the camera aperture 104.

[0019] 2 and 2A, shown is an image projection device 200 mounted on the mobile device 100 of FIG 1, with FIG 2A providing a cross-sectional view of the image projection device 200 at line AA. The body 202 of the image projection device 200 is mounted on the mobile device 100 and has an aperture 210 that is aligned with the camera flash 102. A slide transparency 402 is aligned with the aperture 210 and illuminated by the camera flash 102. A magnifying lens 240 magnifies the illuminated slide transparency 402 onto a projection surface, such as a wall, ceiling, or projection screen.

[0020] The body 202 of the image projection device 200 preferably includes an attachment mechanism 220 for attaching the body 202 to the mobile device 100. The attachment mechanism 220 may include a mechanical clamp as shown in FIG. 2A, which may be made of an elastic material that corresponds to the thickness of the mobile device 100. In some embodiments, the projection device 200 may be embodied as a conventional mobile phone protective case that functions as an attachment mechanism, such as a case that surrounds the edges and / or back of the mobile phone. In some embodiments, the attachment mechanism 220 may include a butterfly clip that is separate from the body 202. The butterfly clip may be spring-loaded and may include a gripping material, such as soft rubber or similar high friction material, on the surface of the clip that engages with the mobile device 100 to limit sliding or movement of the image projection device 200.

[0021] Preferably, the attachment mechanism 220 includes a removable adhesive that is attached to the body 202 to allow installation and removal of the image projection device 200 on the rear surface 106 of the mobile device 100. The removable adhesive may include a nano-adhesive material that is attached to the mating surface of the body 202. The surface of the nano-adhesive material has thousands of microscopic craters that function by creating many partial vacuums between the adhesive and the rear surface 106 of the mobile device 100. The nano-adhesive material is not pressure sensitive, reattaches repeatedly, and leaves no residue on the mobile device. To remove the image projection device 200 from the mobile device 100, simply pull or twist to break the attachment. Wiping the nano-adhesive adhesive material with a wet tissue will remove any debris from the craters and restore the adhesive properties.

[0022] The body 202 is further provided with a slide frame receiving slot 230 shaped to receive a slide frame (as shown in FIGS. 4-6) that houses several slide transparencies. The slide frame may be circular, rectangular, or other shape, and the slide frame receiving slot 230 has a corresponding shape to accommodate the slide frame. To place the slide frame transparency within the aperture 210, the slide frame receiving slot 230 is oriented transverse to the aperture 210. The slide frame is placed in the slide frame receiving slot 230 to align one of the slide transparencies with the camera flash 102 and the aperture 210. The camera flash 102 illuminates the slide transparency 402 within the aperture 210 under the control of the mobile device 100. The slide frame receiving slot 230 may be formed within the body 202 as shown in FIG. 2A or in a passage on the rearward facing surface of the body 202. The location of the slide frame receiving slot 230 relative to the body 202, the camera flash 102, and the magnifying lens 240 can be selected to optimize image projection quality.

[0023] A magnifying lens 240 is aligned with the aperture 210 and is positioned at the front of the body 202 of the image projection device 200. The magnifying lens 240 is positioned between the illuminated slide transparency and the projection surface. The magnifying lens 240 magnifies the slide transparency illuminated by the camera flash 102 for projection onto a projection surface such as a wall or ceiling. Although a simple biconvex lens is shown for illustrative purposes, one of ordinary skill in the art will have suitable lens designs to magnify and project the slide transparency. This may include compound lens designs requiring more than one lens.

[0024] Some embodiments of the image projection device 200 may further include a focus adjustment mechanism 260 that houses the magnifying lens 240. The focus adjustment mechanism 260 may allow axial translation of the magnifying lens 240 relative to the aperture 210 to change the distance between the illuminated slide transparency 402 and the magnifying lens 240 to change the magnification or focus of the projected image. The focus adjustment mechanism 260 may include a telescoping or screw-type configuration that allows movement of the magnifying lens 240. In a compound lens design utilizing more than one lens, only one lens is movable by the focus adjustment mechanism 260.

[0025] A preferred embodiment of the image projection device 200 may also include a flash adjuster 250 aligned with or positioned within the aperture 210 between the camera flash 102 and the slide transparency. The flash adjuster 250 is positioned on the opposite side of the slide frame receiving slot 230 from the magnifying lens 240 so that the light path from the camera flash 102 passes through the flash adjuster 250, then through the slide transparency, and finally magnified by the magnifying lens 240. The flash adjuster 250 helps provide proper and complete illumination of the slide transparency 402. The flash adjuster 250 may include, for example, a light diffusing material, or an optical condenser such as a collimating lens (e.g., a plano-convex lens), or a combination thereof. For example, a plano-convex lens may be used so that the incoming LED light beam from the camera flash 102 is formed into a parallel beam when it strikes the slide transparency, improving the clarity of the projected image. In an embodiment used to project photo-quality slides, a flash adjuster should be used to obtain adequate clarity of the projected image.

[0026] Aperture 210 may have a variety of shapes. Aperture 210 may be circular, for example, to accommodate a circular magnifying lens 240. Aperture 210 may have a shape similar to that of a slide transparency in a slide frame, which may be circular, rectangular, or any other shape, such that slide transparency 402 completely fills aperture 210. Aperture 210 may be cone-shaped or similarly have a size that increases from the rear surface of body 202 adjacent camera flash 102 to the front surface of body 202.

[0027] Some embodiments of the image projection device 200 may be powered to provide additional functionality. Power is obtained by coupling to the mobile device 100, such as through a USB charging port or a Lightning connector for devices manufactured by Apple Inc. Other embodiments of the image projection device 200 may further include a battery to provide power. In some embodiments, the body 202 may include a battery that provides auxiliary power to the mobile device 100 through a charging port. For example, the image projection device 200 may be embodied in a mobile phone case that includes an auxiliary battery similar to those manufactured by mophie inc. The auxiliary battery may also be useful to supplement increased power demands due to continued use of the camera flash 102.

[0028] The image projection device 200 may be coupled to the mobile device 100 by a communication interface. For example, the mobile device 100 may provide instructions regarding slide advancement or focus adjustment via the same interface as the power source (e.g., micro USB or Lightning) or another interface if the image projection device 200 is self-powered (e.g., headphone / microphone jack of the mobile device 100, wireless communication such as Bluetooth or NFC).

[0029] In some embodiments, the image projection device 200 includes a slide decoder that can be used to identify the slide frame and further identify the particular slide transparency within the aperture 210. The slide decoder can include electronics that require power. The slide decoder can include, for example, a Near Field Communication (NFC) transceiver capable of reading one or more radio frequency tags embedded in the slide frame. Decoding information identifying the slide transparency 400 and / or slide frame 402 can be communicated to the mobile device 100 via the communications interface. Other methods of encoding information on slide frames and slide transparencies and such methods of decoding in slide decoder embodiments are described with respect to FIGS. 4-6.

[0030] In other embodiments of the image projection device 200, a slide decoder may be provided by the mobile device 100, either alone or in conjunction with slide decoding functionality provided by the image projection device. For example, an NFC transceiver in the mobile device 100 may identify a particular slide frame, and a slide decoder in the image projection device 200 may identify a particular slide transparency. Figures 3-6 provide examples where the camera of the mobile device 100 may act as a slide decoder.

[0031] A motorized embodiment of the image projection device 200 may include a slide advance motor that is coupled to the slide frame (e.g., using a gear arrangement). The slide advance motor moves the slide frame within the slide frame receiving slot 230 to position the next slide transparency. The image projection device 200 may include buttons to control the slide advance motor, such as forward and back buttons. In other embodiments, the mobile device 100 can provide instructions to the slide advance motor that control which slide transparency is within the aperture 210.

[0032] A motorized embodiment of the image projection device 200 may also include a focus adjustment motor coupled to the focus adjustment mechanism 260 to adjust the position of the magnifying lens 240. Again, this may be controlled by a button on the image projection device 200 or by the mobile device 100. The camera of the mobile device 100 may capture the projected image, and the mobile device 100 may determine whether the captured image is in focus, for example, by using an edge detection algorithm. The mobile device 100 may provide instructions to the focus adjustment motor based on this information. The mobile device 100 may periodically monitor the projected image using the camera to maintain focus of the projected image. The mobile device 100 may also rely on information from an on-board motion sensor / accelerometer to consider whether to reevaluate focus adjustment by the focus adjustment motor.

[0033] Some embodiments of the image projection device 200 may include electronic stabilization to eliminate or reduce the effect of hand movement on the projected image. An embodiment of the electronic stabilization includes a handle that houses a motion sensor (e.g., an accelerometer) and is coupled to the body 202 of the image projection device 200 via one or more motors to provide three degrees of freedom of movement. When movement is detected by the motion sensor, the handle controls the motors to counteract the movement and maintain the body 202 in a stable position.

[0034] 3A and 3B, shown are front and back exploded perspective views of an image projection device 300 for receiving a circular slide frame as shown in FIG 4. The body 302 of the image projection device 300 defines an aperture 310 that interacts with a slide frame receiving slot 330. The mounting mechanism 320 is a nano-adhesive material that is mounted to the rear surface of the body 302 of the image projection device 300.

[0035] The slide frame receiving slot 330 receives a slide frame alignment feature 332 for mating with the center of the rotating slide frame 400. The center of the circular slide frame 400 has a hole, recess, protrusion, or axis that engages with the slide frame alignment feature 332 to position the circular slide frame 400 in place and allow it to rotate. Figure 3A illustrates a flexible protrusion 332 that can mate with a hole or recess in the center of the circular slide frame 400.

[0036] The exploded view illustrates an embodiment with a focus adjustment mechanism that allows movement of the magnifying lens 340. The lens slide 362 can move forward and backward within the aperture 310. The lens mount 364 clips onto the lens slide 362 and holds the magnifying lens 340 with a press fit between the lens mount 364 and the lens slide 362.

[0037] The embodiment of Figures 3A and 3B relies on the camera of the mobile device 100 to provide some slide decoding functionality. The body 302 is designed to cover the camera module of the mobile device 100 and includes a camera opening 380 and a light passage 382 on the rear side of the body 302. The slide frame receiving slot 330 opens into the camera opening 380 to allow the slide decoding block 410 (see Figure 4) of the slide frame 400 to be captured by the camera of the mobile device 100. Light from the camera flash 102 is transmitted to the camera opening 380 via the light passage 382, ​​allowing the camera of the mobile device 100 to capture the slide encoding block 410 associated with the currently illuminated slide transparency 402. The light passage 382 is free space or some light-transmitting material (e.g., clear plastic or glass).

[0038] 4, shown is a front view of a circular slide frame 400 designed to function with the image projection device 300 shown in FIGS. 3A and 3B. The slide frame 400 includes slide coding information in a coding block 410 adjacent to a corresponding slide transparency 402. The coding information in the coding block 410 identifies the slide transparency 402 being projected on the mobile device 100 and enables the mobile device 100 to interface with the projected image (such as a book or movie clip, for example, to stream associated media such as audio and video, e.g., songs, audio dialogue, sound effects, etc., on the mobile device video display).

[0039] The slide frame 400 may include a notch or indentation 404 that engages with a corresponding structure in the slide frame receiving slot 330. This provides mechanical feedback to the user indicating that the slide transparency 402 is in proper alignment. For example, the slide frame receiving slot 330 may have a flexible detent in the slot that engages with the notch / indentation 404 in the slide frame 404 to align the slide frame within the aperture 310. The flexible detent may be a flexible plastic or spring based. Other embodiments have a rigid detent, where the slide frame is made of a flexible material, allowing movement and alignment of the slide transparency 402 within the aperture 310. In some embodiments, an audible feedback (e.g., a click) is provided when the detent engages with the notch / indentation 404. Some embodiments of the slide frame 400 may include a notch with a moderate slope on one edge and a much steeper slope on the other edge that mates with a pawl or detent in the slide frame receiving slot (e.g., through the use of a ratchet / pawl mechanism) to limit movement of the slide frame 400 to a single direction.

[0040] The coding information encoded in the coding block 410 can identify the slide transparency 402 currently being projected. Many different coding methods can be used to code information into the coding block 410. For example, in FIG. 4, the coding block 410 is a color transparency that can be detected by the camera of the mobile device 100 when used in an embodiment of the image projection device 300. Light from the camera flash 102 illuminates the color transparency coding block 410 through the light path 382, ​​and the color can be determined by the mobile device 100 through the camera. Each slide transparency 402 in the slide frame 400 can have a unique color associated with it.

[0041] Referring now to FIG. 5, shown is an embodiment of a rectangular slide frame 500 that includes coding information in coding blocks that are on each slide transparency 502 itself (i.e., not in a coding block separate 410 from the slide transparency 402 as in FIG. 4). FIG. 5 illustrates several different coding methods, but preferably only a single type of coding is used on the slide frame. In the first two slide transparency examples, the coding blocks encode information using a barcode embedded in the slide transparency 502 that can be detected by the camera of the mobile device 100 when the slide transparency 502 is projected onto a projection surface. The coding blocks can include any type of barcode (including linear barcodes, 2D barcodes such as QR Codes, and barcodes that include color). For example, a linear barcode 512 and a QR code 514 are shown embedded in the slide transparency 502 of FIG. 5. The slide frame 500 includes indentations 504 that can mate with detents or pins in a slide frame receiving slot to aid in aligning the slide frame 500 within the aperture of the image projection device.

[0042] In some embodiments, the coding information may include the slide transparency image itself so that the mobile device 100 can use image processing to identify the projected image from several possible slide transparencies. In these embodiments, the coding block may be considered to be the slide transparency 502 itself. For example, the mobile device 100 may process the projected image captured by the camera to obtain a signature of the projected image, and then compare this signature with signatures from a database, either on the mobile device 100 or on a networked server, to identify a particular slide transparency or an event to be triggered by the mobile device 100. The example sun picture 515 provides a unique signature that may help identify a particular slide transparency to the mobile device 100. For example, an edge detection algorithm may be used to identify the projected slide on the projection surface, and a further edge detection algorithm may be used on the identified projected slide to obtain an edge detection matrix that may be compared to edge matrices of known slide transparencies.

[0043] The coding information in the coding block is either unique for all possible slide transparencies (i.e., a globally unique identifier) ​​or unique only for slide transparencies of a given slide frame (e.g., identifying slide numbers 1 to 10). Depending on the coding method used, it may be difficult to provide a globally unique identifier for each slide transparency. For example, if a color coding method such as that of FIG. 4 is used, it is only possible to accurately code a certain number of colors that may be detected depending on the distance from the coding block to the camera, the amount of light, and the variability between mobile device cameras from different manufacturers. In those embodiments that do not include globally unique coding information in the coding block 410, the slide frame 400 may include a slide frame coding block 420 that uniquely identifies the slide frame 400, such that a combination of the coding block 410 and the slide frame coding block 420 may uniquely identify a particular slide transparency 402. The slide frame identifier 420 may include text written on the slide frame 400 (requiring a user to have the mobile device 100 identify the slide frame through an input device) or may also include a near field communication (NFC) tag that is detected, for example, by an NFC sensor in the mobile device 100.

[0044] Referring now to FIG. 6, shown is a rectangular slide frame 600 with coding blocks adjacent to each slide transparency 602. Again, a number of coding methods are shown on the slide frame 600 for illustrative purposes. The slide frame 600 is designed so that the coding blocks are located close to a slide reader of the mobile device 100, such as the mobile device camera or NFC transceiver. Focusing directly on the coding blocks (rather than the projected coding blocks of FIG. 5) limits the resolution (or amount of coded information) that can be reliably detected by the mobile device camera. The mobile device 100 may configure the camera to focus on closely located coding blocks. The slide frame 600 also includes several protrusions 606 that can engage corresponding recesses in the slide frame receiving slot to aid in alignment of the slide frame 600 within the aperture of the image projection device. Examples shown in FIG. 6 include encoding information including color using color transparency 616, encoding information into a barcode such as a linear barcode 617 or a QR code 618, and encoding information into an NFC tag 619.

[0045] Referring to FIG. 7, shown is a block diagram of a mobile device 700 that may include a processor 710, a memory 720, a rear camera flash 730, a rear-facing camera 740, a display 750, a speaker 760, a slide interpreter 770, and an input device 780. A communication interface 790 may be provided for the mobile device 700 to communicate with other computing devices (including, for example, computer-based embodiments of an image projection device) via wired or wireless communication or via a communication network. As mentioned above, the communication interface 790 may include a charging port of the mobile device 700, Wi-Fi, or Bluetooth. The mobile device 700 may use the processor 710 to execute programs stored in the memory 720 to interact with (receive input and provide output from) the other components illustrated in FIG. 7. The rear camera flash 730 and the rear-facing camera 740 may be located on the rear of the mobile device 700, such as that shown in FIG. 1. The mobile device 700 controls a rear camera flash 730 to act as a projection light source for the image projection device 200 shown in Figure 2. Examples of the mobile device 700 may include a mobile computing device, such as a mobile phone, a laptop computer, or a tablet computing device.

[0046] The mobile device 700 may provide audio and video through a speaker 760 and a display 750. A user may interact with the mobile device 700 and provide input through an input device 780, which may include a keyboard, buttons, or a touch screen interface. Input received through the input device 780 may be used to initiate the transmission of instructions (e.g., advance to the next slide, adjust focus, etc.) to an associated image projection device.

[0047] The slide decoder 770 decodes the coded information of a coding block (such as coding block 410 or slide frame coding block 420) on the slide frame to aid in identifying a particular slide transparency. The slide decoder 770 may include a rear-facing camera 740. The slide decoder 770 may also be a wireless receiver, such as a near-field communication transceiver.

[0048] 8, shown is a flow chart diagram of a method 800 for triggering an event at a mobile device based on a change in an illuminated slide at the image projection device 200. The method 800 may be used to coordinate the playback of multimedia corresponding to a currently projected slide transparency. Initially, at step 802, a slide frame is identified. This step may utilize a slide decoder 770 of the mobile device 700 to decode a slide frame coding block, such as slide frame coding block 420. In other embodiments, this step may include a user of the mobile device 700 providing input through the input device 780 to identify the slide frame, for example, by selecting an application associated with the slide frame or by selecting a story within the application associated with the slide frame. In other embodiments, identifying the slide frame may also include the slide decoder 770 decoding a coding block associated with any one of the slide transparencies.

[0049] Next, in step 804, a change in the illuminated or projected slide transparency is detected. This may include detecting a change in the coding block associated with the slide transparency detected by the slide decoder 770. This may include the mobile device 700 receiving an indication from the input device 780 to advance the next slide or a communication from the image projection device 200 through the communication interface 790 that the slide frame has been advanced. The image projection device 200 may also include a switch in the slide frame receiving slot 230 that is activated each time a slide frame is advanced, and this switch information may be communicated to the mobile device 100 to detect the change in step 804.

[0050] In step 806, an event is initiated on the mobile device 100 that is associated with the currently illuminated slide transparency. An event on the mobile device 100 may relate to playing sound through the speaker 760 or updating the display 750. An event may also relate to operating the rear camera flash 730, for example, switching it off and on to mimic lighting.

[0051] An example of the operation of the image projection device 200 and method 800 includes use for a storybook or nursery rhyme. The slide frame contains a series of image transparencies associated with the storybook or nursery rhyme, and the mobile device executes an associated app that aids in the storytelling (e.g., sounds such as music or narration, a story displayed on the mobile device display). The associated app activates the mobile device's camera flash to illuminate the slide transparency and receives information identifying the slide transparency and / or slide frame through a slide detection module (e.g., using the mobile device's camera or NFC sensor). The mobile device detects the change in the encoded information as the slide advances and triggers an event in the associated app executing on the mobile device (e.g., turning a page in the book, starting an audiobook audio associated with the book page, playing a sound effect or narration). The associated app also allows the user to select a language, and the associated app can retrieve the associated content or story in the selected language.

[0052] The system, apparatus and method embodiments described herein may be embodied in hardware or software, or a combination thereof. Some of the embodiments described herein may be embodied in a computer program executing on a programmable computer, each computer including at least one processor, computer memory (including volatile or non-volatile memory), at least one input device, and at least one output device. For example, and without limitation, the programmable computer may be a server class computer having multiple processors and at least one network interface card. The program code operates on input data to perform the functions described herein and generate output data.

[0053] Although exemplary embodiments have been described herein, it should be understood that the present invention is not limited to the disclosed embodiments. The present invention is intended to include various modifications and equivalent arrangements within the spirit and scope of the appended claims, and the scope of the claims is to be interpreted to include all such modifications and equivalent structures and functions.

[0054] [Appendix 1] 1. An image projection device for use in conjunction with a mobile device having a camera flash, comprising: a body defining an aperture, the body having an attachment mechanism adapted to attach to the mobile device and align the aperture with the camera flash; a slide frame receiving slot in the body, the slide frame receiving slot being transverse to the aperture; a magnifying lens aligned with the aperture, the magnifying lens being disposed at a front end of the body; An image projection device comprising: [Appendix 2] 2. The image projection device of claim 1, wherein the camera flash illuminates a slide transparency accommodated in the slide frame receiving slot, and the magnifying lens magnifies the illuminated slide transparency and projects the transparency. [Appendix 3] 2. The image projection device of claim 1, further comprising a flash adjuster aligned with the aperture and on an opposite side of the slide frame receiving slot from the magnifying lens. [Appendix 4] 2. The image projection device of claim 1, further comprising a focus adjustment mechanism housing the magnifying lens, the focus adjustment mechanism for axially translating the magnifying lens relative to the aperture. [Appendix 5] 5. The image projection device of claim 4, wherein the focus adjustment mechanism is one of an extension mechanism and a screw mechanism. [Appendix 6] 5. The image projection device of claim 4, wherein the body further includes a motor and is electrically coupled to the mobile device to receive instructions, the motor being coupled to the focus adjustment mechanism, and the mobile device having a camera to provide instructions to the motor to adjust focus based on a projected image detected by the camera. [Appendix 7] 2. The image projection device of claim 1, wherein the attachment mechanism is one of a clamp or a butterfly clip. [Appendix 8] 8. The image projection device of claim 7, wherein the mounting mechanism has a surface that mates with the mobile device, the surface including a high friction material that limits movement of the image projection device. [Appendix 9] 2. The image projection device of claim 1, wherein the mounting mechanism is a mobile device case. [Appendix 10] 2. The image projection device of claim 1, wherein the slide frame receiving slot has a flexible detent that interacts with a notch in the slide frame to align the slide frame within the aperture. [Appendix 11] 11. The image projection device of claim 10, wherein the flexible detent interacting with the notch provides one of mechanical feedback and audible feedback. [Appendix 12] 2. The image projection device of claim 1, wherein the body further includes a motor and is coupled to the mobile device to receive instructions, and the motor is coupled to the slide frame to advance the slide frame with instructions from the mobile device. [Appendix 13] 2. The image projection device of claim 1, wherein the body further defines a camera opening for alignment with a camera of the mobile device, the slide frame receiving slot is oriented transverse to the camera opening, and an encoding block of the slide frame is positioned in the camera opening for detection by the camera of the mobile device. [Appendix 14] 14. The image projection device of claim 13, wherein the body further includes a light passage coupling the aperture to the camera opening. [Appendix 15] At least one slide transparency; coded information associated with said at least one slide transparency; A slide frame that includes: [Appendix 16] 16. The slide frame of claim 15, further comprising at least one coding block adjacent to the at least one slide transparency, the coding block having the coding information. [Appendix 17] 17. The slide frame of claim 16, wherein the at least one coding block is one of a bar code, a color, and a near field communication tag. [Appendix 18] 16. The slide frame of claim 15, wherein the encoding information is encoded into the image of the at least one slide transparency. [Appendix 19] 19. The slide frame of claim 18, wherein the encoded information is encoded as a bar code. [Appendix 20] 2. A method of operating an image projection device according to claim 1 in relation to a mobile device having a camera flash, comprising: identifying changes in the encoded information of the slide frames detected by a slide decoder; associating the change in the coded information with an event; and initiating the event; and The method includes: [Appendix 21] 21. The method of claim 20, wherein the event is one or more of: a change in the video display of the mobile device; and playing audio through a speaker of the mobile device. [Appendix 22] 21. The method of claim 20, wherein the slide decoder further comprises one of a camera and a near field communication sensor of the mobile device. [Appendix 23] 21. The method of claim 20, wherein the slide decoder includes a camera of the mobile device, and identifying an alteration to the encoded information further includes capturing an image with the camera and comparing the image to a previously captured image to determine whether the slide transparency has been altered. [Appendix 24] 24. The method of claim 23, further comprising processing the image captured by the camera to obtain a signature of the projected slide transparency and comparing the signature to a database to associate the signature with either a particular slide transparency or one or more events. [Explanation of symbols]

[0055] 100 Mobile Devices 102 Camera Flash 104 Camera Aperture 106 Rear 200 Image projection device 202 Main Body 210 Aperture 220 Attachment Mechanism 230 Slide frame receiving slot 240 Magnifying Lens 250 Flash Adjuster 260 Focus adjustment mechanism 300 Image Projection Device 302 Main unit 310 Aperture 320 Mounting Mechanism 330 Slide frame receiving slot 332 Slide frame alignment mechanism 340 Magnifying Lens 362 Lens Slide 364 Lens mounting part 380 Camera opening 382 Light passage 400 Rotating Slide Frame 402 Slide Transparency 404 Notch / Depression 410 coding block 420 Slide Frame Coding Block 500 Rectangular Slide Frame 502 Slide Transparency 504 Hollow 512 Linear Barcode 514 QR Code 515 Sun Painting 600 Rectangular Slide Frame 602 Slide Transparency 606 Protrusion 616 Color Transparency 617 Linear Barcode 618 QR Code 619 NFC Tags 700 Mobile Devices

Claims

1. 1. An image projection device for use in conjunction with a mobile device having a camera flash, comprising: a body defining an aperture, the body having an attachment mechanism for attachment to the mobile device to position the aperture to receive light from the camera flash; a slide frame receiving slot in the body arranged to receive the slide frame and position the slide on the slide frame with the aperture such that illumination from the camera flash transmits light through the slide along the aperture; a magnifying lens positioned in front of the slide frame such that light from the camera flash is projected through the slide frame receiving slot, the slide, and the magnifying lens; a flash adjustment within the aperture on an opposite side of the slide frame receiving slot from the magnifying lens; An image projection device comprising:

2. 2. The image projection device of claim 1, further comprising a focusing mechanism housing said magnifying lens, said focusing mechanism for axially translating said magnifying lens relative to said aperture.

3. The image projection device according to claim 2 , wherein the focus adjustment mechanism is one of a telescopic mechanism and a screw mechanism.

4. 3. The image projection device of claim 2, wherein the body further includes a focus adjustment motor and is electrically coupled to the mobile device to receive instructions, the motor being coupled to the focus adjustment mechanism, and the mobile device has a camera to provide instructions to the motor to adjust focus based on the projected image detected by the camera.

5. The image projection device of claim 1 , wherein the mounting mechanism is a mobile device case.

6. The image projection device according to claim 1 , wherein the body further includes a motor, coupled to the mobile device to receive instructions, and the motor is coupled to the slide frame to advance the slide frame with instructions from the mobile device.

7. 2. The image projection device of claim 1, wherein the body further defines a camera opening for alignment with a camera of the mobile device, the slide frame receiving slot is in front of the camera opening so that light from the camera is projected through the slide frame, and an encoding block of the slide frame is positioned in the camera opening for detection by the camera of the mobile device.

8. The image projection device of claim 7 , wherein the body further comprises a light passageway coupling the aperture to the camera opening.

9. 1. An image projection device for use in conjunction with a mobile device having a camera flash, comprising: a body defining an aperture, the body having an attachment mechanism for attachment to the mobile device to position the aperture to receive light from the camera flash; a slide frame receiving slot in the body arranged to receive the slide frame and position the slide on the slide frame with the aperture such that illumination from the camera flash transmits light through the slide along the aperture; a magnifying lens positioned in front of the slide frame such that light from the camera flash is projected through the slide frame receiving slot, the slide, and the magnifying lens; The attachment mechanism is either a clamp or a butterfly clip. Image projection device.

10. 10. The image projection device of claim 9, wherein the mounting mechanism has a surface that mates with the mobile device, the surface including a high friction material that limits movement of the image projection device.

11. 1. An image projection device for use in conjunction with a mobile device having a camera flash, comprising: a body defining an aperture, the body having an attachment mechanism for attachment to the mobile device to position the aperture to receive light from the camera flash; a slide frame receiving slot in the body arranged to receive the slide frame and position the slide on the slide frame with the aperture such that illumination from the camera flash transmits light through the slide along the aperture; a magnifying lens positioned in front of the slide frame such that light from the camera flash is projected through the slide frame receiving slot, the slide, and the magnifying lens; the slide frame receiving slot has a flexible detent that interacts with a notch in the slide frame to align the slide frame within the aperture; Image projection device.

12. 1. A method of operating an image projection device for use in conjunction with a mobile device having a camera flash, comprising: The image projection device includes: a body having a slide frame receiving slot for receiving a slide frame including a plurality of slide transparencies and encoded information associated with at least one of the plurality of slide transparencies; an aperture positionable to receive light from the camera flash and transmit the light through at least one of the plurality of slide transparencies; a lens positionable to project light transmitted through at least one of the plurality of slide transparencies; The method comprises: positioning the slide frame such that a first slide transparency from the plurality of slide transparencies is positioned at the aperture to transmit light through the first slide transparency; detecting first encoded information associated with the first slide transparency; generating a first output from the mobile device based on the first coded information, the first output being selected from a group of outputs consisting of an audio output and a visual output; positioning the slide frame such that a second slide transparency from the plurality of slide transparencies is positioned at the aperture to transmit light through the second slide transparency; detecting second encoded information associated with the second slide transparency; generating a second output from the mobile device based on the second coded information, the second output being selected from a group of outputs consisting of an audio output and a visual output, the second output being different from the first output; A method comprising:

13. 13. The method of claim 12, wherein the steps of detecting the first coded information and detecting the second coded information are performed via a slide decoder selected from a group of slide decoders consisting of a camera and a near-field communication sensor of the mobile device.

14. 14. The method of claim 13, wherein the slide reader comprises a camera of the mobile device, the mobile device being programmed to capture an image with the camera and compare the image to a previously captured image to determine whether the slide transparency has been altered.

15. 1. A combination for use in connection with a mobile device having a camera flash, comprising: a slide frame having a first side, a second side, and an edge, the slide frame having a plurality of slides thereon; 1. An image projection device, comprising: a body defining an aperture, the body being attachable to the mobile device to position the aperture to receive light from the camera flash; a slide frame receiving slot in the body positioned to receive the slide frame to position one of the plurality of slides on the slide frame at the aperture such that illumination from the camera flash transmits light through the slide along the aperture; and at least one of a first side and a second side of the slide frame having a plurality of features thereon, each slide frame capable of mating with a corresponding feature of the slide frame receiving slot to align the slide frame to position one of the plurality of slides on the slide frame at the aperture such that illumination from the camera flash transmits light through the slide along the aperture; a magnifying lens positioned in front of the slide frame such that light from the camera flash is projected through the slide frame receiving slot, the slide, and the magnifying lens; An image projection device comprising: A combination that includes:

16. 1. A slide frame in combination with an image projection device that is removably attached to a smartphone or tablet computing device having a camera and a camera flash, comprising: The image projection device, a body defining an aperture, the body having an attachment mechanism for removably attaching the body to the smartphone or tablet computing device such that the aperture is positioned to receive light from the camera flash; and a slide frame receiving slot in the body arranged to receive a slide frame and position one of the plurality of slide transparencies on the slide frame at the aperture such that illumination from the camera flash transmits light through the one of the plurality of slide transparencies along the aperture; the body further includes a camera opening and a light passageway coupling the camera opening to the aperture; the camera opening is alignable with the camera when the aperture is aligned with the camera flash; the image projection device including a magnifying lens positioned in front of the slide frame such that light from the camera flash is projected through the slide frame receiving slot, the slide, and the magnifying lens; the slide frame includes encoded information associated with each of at least a portion of the plurality of slide transparencies; In use, when the slide frame is placed in the image projection device with one of the slide transparencies aligned with the aperture, coded information associated with one of the slide transparencies is captureable by the camera through the camera opening and readable by an application on the smartphone or tablet computing device, and instructs the smartphone or tablet computing device to emit at least one form of output selected from the group of outputs consisting of an audio output and a visual output; the at least one form of output is selected based on detection by the application of a change in the encoded information based on a slide transparency from at least a portion of a plurality of slide transparencies being aligned with the camera flash. Slide frame.

17. 17. The slide frame of claim 16, further comprising at least one coding block adjacent to said at least one slide transparency, said coding block having said coding information.

18. 20. The slide frame of claim 17, wherein the at least one coding block is one of a bar code, a color, and a near field communication tag.

19. 17. The slide frame of claim 16, wherein the encoded information is encoded into an image of the at least one slide transparency.

20. 17. The slide frame of claim 16, wherein the encoded information is encoded as a bar code.

Images