HEAD-MOUNTED DISPLAY APPARATUS AND CONTROL METHOD THEREOF

A head-mounted display apparatus and control method are provided. The apparatus includes a display unit, a signal processing unit processing an image signal to display an image on the display unit, a shutter unit performing a shutter operation to allow selective transmission of external light for both eyes of a user, a camera detecting and taking an image of an external environment of the head-mounted display apparatus, and a controller maintaining transmission of the shutter unit transmitting external light at preset first transmittance when the image is displayed on the display unit, and adjusting the transmission of the shutter unit to second transmittance higher than the first transmittance if the camera detects an external device while the image is displayed on the display unit.

DETAILED DESCRIPTION

FIG. 1illustrates a display apparatus1according to an exemplary embodiment.

As illustrated inFIG. 1, the display apparatus1according to an exemplary embodiment is a head-mounted display apparatus1mounted on a user's head. The display apparatus1may have a similar shape to a pair of glasses and includes a frame10configured to be put on the head or ears of a user and glass units20supported by the frame10and covering views of both left and right eyes of the user.

The frame10and the glass units20may be formed in various shapes with various materials, without being particularly limited. The frame10and the glass units20form an interior space to accommodate different elements of the display apparatus1. The glass units20may be formed of a transparent material to enable light transmission.

An exemplary configuration of the display apparatus1is described in detail with reference toFIG. 2.

FIG. 2illustrates an exemplary display apparatus1. Components of the display apparatus1illustrated inFIG. 2may be accommodated in the frame10or the glass units20ofFIG. 1. Accommodation forms or methods of these components change based on shapes of the frame10and the glass units20and do not limit the scope of an exemplary embodiment.

The elements of the display apparatus1illustrated inFIG. 2are illustrative of an exemplary embodiment, but are not limited to the same.

As illustrated inFIG. 2, the display apparatus1includes a signal reception unit110receiving an image signal from the outside, a signal processing unit120processing an image signal received by the signal reception unit110according to a preset image processing process, a display unit130displaying an image based on the image signal processed by the signal processing unit120, a shutter unit140conducting a shutter operation to allow selective transmission of external light for both eyes of a user, a communication unit150capable of communicating with various external devices (not illustrated), a user input unit160generating a preset control command by manipulation of the user, a storage unit170storing data, a power supply unit180supplying operating power to each component of the display apparatus1, and a controller1900controlling operations, e.g., general operations of the display apparatus1.

The display apparatus1may include a camera210taking/picking up a video/still image of an external environment, a microphone220detecting a sound of the external environment, and earphones230outputting the sound.

The signal reception unit110receives an image signal/image data transmitted from the outside via a wired, e.g., cable and/or wireless connection and transmits the signal/data to the signal processing unit120and/or the controller190. For example, the signal reception unit110may receive a radio frequency (RF) signal transmitted from a broadcasting station (not illustrated) wirelessly or receive image signals in accordance with composite video, component video, super video, SCART, high definition multimedia interface (HDMI), DisplayPort, unified display interface (UDI), or wireless HD standards via a cable.

Although the signal reception unit110is described as a separate component from the communication unit150in the present embodiment, the signal reception unit110and the communication unit150may be integrated as a communication interface.

The signal processing unit120performs various image processing processes on an image signal received by the signal reception unit110. The signal processing unit120outputs a processed image signal to the display unit130, so that an image based on the image signal may be displayed on the display unit130.

The signal processing unit120may perform various types of image processing processes, without being limited to, for example, decoding corresponding to an image format of image data, de-interlacing to convert an interlaced image signal into a progressive form, scaling to adjust image data to a preset resolution, noise reduction to improve image quality, detail enhancement, and frame refresh rate conversion.

The signal processing unit120may be provided as an integrated multi-functional component, such as a system on chip (SOC), or as an image processing board (not shown) formed by mounting components that independently conduct individual processes on a printed circuit board and be embedded in the display apparatus1.

The display unit130displays an image based on an image signal processed by the signal processing unit120to be formed close to both eyes of the user. A configuration of the display unit130to display an image is described.

The shutter unit140conducts a shutter operation to selectively allow/block transmission of external light for at least one eye, e.g., both eyes of the user. The shutter unit140may be configured as liquid crystal shutter glass having light transmittance transmission adjusted by the controller190and is installed on an outside of the glass units20to cover both eyes of the user.

The shutter operation conducted by the shutter unit140may be selective with respect to each eye of the user or may operate in a similar manner with respect to both eyes of the user. For example, the shutter unit140may conduct a shutter operation such that light is blocked for the left eye of the user and light is transmitted for the right eye of the user. Alternatively, the shutter unit140may conduct a shutter operation such that light is blocked for the right eye of the user and light is transmitted for the left eye of the user. Alternatively, the shutter unit140may conduct a shutter operation such that light is blocked for both right and left eyes of the user or transmitted for both right and left eyes of the user. Alternatively, the shutter unit140may transmit or block light for both eyes of the user, adjusting transmission of the external light.

The communication unit150may perform bidirectional communications with various types of external devices (not illustrated) via a wired and/or wireless connection. The communication unit150may include a communication interface along with the signal reception unit110depending on a design. In an exemplary embodiment, the communication unit150may perform wireless communications based on bidirectional RF/wireless communication standard, such as RF and Bluetooth.

The user input unit160generates a preset control command and transmits the command to the controller190by manipulation of the user. For example, the user input unit160may be configured as an input key pad (not illustrated) installed on the frame10or a touch screen (not illustrated) or touch sensor (not illustrated) on the glass units20.

The user input unit160may be configured as an external device (not illustrated), such as a remote controller separated from the display apparatus1or a mobile phone. The user input unit160may communicate with the communication unit150to transmit the control command to the controller190.

The storage unit170stores unlimited data according to control of the controller190. The storage unit170is configured as a nonvolatile memory, such as a flash memory and a hard disk drive. The storage unit170may be accessed by the controller190, and the data stored in the storage unit170may be read/recorded/revised/deleted/updated by the controller190.

The power supply unit180supplies power, e.g., direct-current (DC) power for operations of general components of the display apparatus1. The power supply unit180may be configured as a primary battery or a secondary battery, for example, a secondary battery chargeable with an external power source for utilization. Power supply of the power supply unit180may be controlled by the controller190, wherein, for example, whether to output power to a particular element, an output voltage level, and output duty adjustment are controlled.

The camera210may be installed on an outside of the frame10and detects and takes an image of an external environment of the display apparatus1. The camera210may take an image of the external environment at particular time to generate a still image or take images of the external environment for a preset time to generate a video.

The camera210may monitor the external environment for a predetermined time. For example, when the user wearing the display apparatus1moves their eyes or turns their head, the camera210may newly detect an electronic device (not illustrated) in the external environment. The camera210informs the controller190that the electronic device40has been detected and transmits a still image/video of the detected electronic device40taken to the controller190.

An exemplary structure of displaying an image on the display unit130is described with reference toFIG. 3.

FIG. 3illustrates a structure of an image displayed by the display unit130being formed in an eye, e.g., the left eye of the user. Since a structure with respect to the left eye of the user and a structure with respect to the right eye of the user are substantially symmetrical on the display unit130, an exemplary embodiment may be applied to the structure of an image being formed in the right eye of the user, and thus descriptions thereof are omitted herein.

As illustrated inFIG. 3, the display unit130includes a display element131presenting an image signal processed by the signal processing unit120as an image, a total reflection mirror133reflecting an image displayed on the display element131, and a translucent mirror135on which an image reflected by the total reflection mirror133may be formed.

A left-eye shutter141covers an outside of a left-eye glass21, thereby selectively controlling transmission of external light to the left eye of the user.

The display element131may be installed in the frame10. The display element131may be configured as an LCD panel and displays an image by the signal processing unit120.

The total reflection mirror133and the translucent mirror135may be installed in the left-eye glass21corresponding to the left eye of the user. The total reflection mirror133may be disposed in the left-eye glass21out of sight of the user and has total reflection characteristics to reflect an image displayed on the display element131. The translucent mirror135may be disposed in a direction of sight of the user and has characteristics of transmitting part of entering light and forming the remaining entering light on the surface as an image.

When the left-eye shutter141allows light transmission and an image is not displayed on the display element131, external light may arrive in the left eye of the user, passing through the left-eye shutter141, the left-eye glass21, and the translucent mirror135. Thus, the user wearing the display apparatus1may perceive the external environment by the left eye.

When an image is displayed on the display element131, the image displayed on the display element131enters the total reflection mirror133(P1). In this process P1, a lens (not illustrated) to adjust optical properties or an image transmission duct (not illustrated) to transmit an image, such as fiber, may be installed in the frame10.

The image reflected by the total reflection mirror133may be formed on the translucent mirror135(P2). The image formed on the translucent mirror135may be perceived by the left eye of the user. When the left-eye shutter141is in a state of allowing light transmission, the user may perceive the external environment through the translucent mirror135, with the image formed on the translucent mirror135.

When it is not easy to perceive an image on the translucent mirror135by external light, the user may operate the left-eye shutter141to block light, thereby preventing interference by the external light.

In this way, the display apparatus1may display an image based on an image signal received from the outside or autonomously stored.

FIG. 4illustrates an exemplary display apparatus ofFIG. 1operating in a synchronous mode, that is, operate in synchronization with an external display apparatus30.

As illustrated inFIG. 4, the display apparatus1performs bidirectional communication with the external display apparatus30, such as a TV, through the communication unit150. When the display apparatus1and the external display apparatus30are paired with each other, various types of signals/data/information may be exchanged therebetween.

When the synchronization signal is received, the display apparatus1controls the shutter operation of the shutter unit140based on the received synchronization signal. The display apparatus1controls the shutter unit140to transmit light for the left eye of the user and to block light for the right eye of the user while a left-eye image is displayed on the external display apparatus30. The display apparatus1may control the shutter unit140to block light for the left eye of the user and to transmit light for the right eye of the user while a right-eye image is displayed on the external display apparatus30. While the left-eye or right-eye images are displayed as mixed on the external display apparatus30, that is, the left-eye or right-eye images are scanned, the display apparatus1may control the shutter unit140to block light for both left and right eyes of the user.

The display apparatus1may control the display unit130to not display an image, or to display an image in another manner.

The display apparatus1according to an exemplary embodiment may operate in a mode among the synchronous modes in which the display apparatus1operates in accordance with a display cycle of external images displayed on the external display apparatus30and an image display mode in which the display apparatus1displays an image based on an image signal processed by the signal processing unit120on the display unit130.

Selection of each mode may be realized by a control signal ordering to switch to a corresponding mode through the user input unit160. Alternatively, the display apparatus1may automatically go to the synchronous mode, e.g., when paired with the external display apparatus30. Alternatively, the display apparatus1may automatically go to the image display mode or a standby mode when released from pairing with the external display apparatus30.

The standby mode may be defined variously and may be designated, for example, as allowing light transmission for both eyes of the user by the shutter unit140and not displaying an image on the display unit130.

An operation of the camera210detecting the electronic device40when the display apparatus1is in the image display mode is described with reference toFIGS. 5 and 6. In an exemplary embodiment, the electronic device40may include a general electronic/electrical device, for example, a TV, a monitor, a set-top box, home appliances, a computer, and a mobile device.

FIG. 5illustrates and exemplary process for the display apparatus1controlling the shutter unit140in the image display mode.

FIG. 6illustrates a screen310when the camera210detects the electronic device40.

As illustrated inFIGS. 5 and 6, while the display apparatus1operates in image display mode, the signal processing unit120processes an image signal to display an image on the display unit130(S100), and the shutter unit140maintains transmission of external light at preset first transmittance for both eyes of the user (S110).

The first transmittance is not limited to a particular value but may be changed variously within a range in which an external light blocking ratio is considered relatively high so that a general user easily perceive an image displayed on the display unit130.

That is, the shutter unit140maintains the first transmittance while an image is displayed on the display unit130, thereby suppressing interference by external light in both eyes of the user and enabling the user to easily perceive the image.

During the image display mode of the display apparatus1, the camera210monitors an external environment (S120). Monitoring of the camera210may be automatically performed when the display apparatus1goes to the image display mode or be activated by input through the user input unit160or a voice instruction through the microphone20after the display apparatus1goes to the image display mode.

The camera210may detect a new electronic device40during monitoring, as illustrated inFIG. 6.

When the electronic device40is detected in the external environment (S130), the camera210transmits a detection result to the controller190. When the electronic device40remains detected for a preset time, the camera210may transmit a detection result to the controller190.

When the electronic device40is detected by the camera20(S130), the controller190adjusts light transmittance of the shutter unit140to second transmittance higher than the first transmittance (S140). That is, when the electronic device40is detected by the camera210as the user turns the head or moves the eyes while an image is displayed, the controller190controls light transmittance of external light through the shutter unit140to be relatively high.

The second transmittance is not limited to a particular value, but may be adjusted variously as long as the second transmittance is higher than the first transmittance.

The controller190controls the shutter unit140to have the second transmittance, and controls an image displayed on the display unit130to remain still or executes control so that an image is not displayed on the display unit130(S150).

Accordingly, the user wearing the display apparatus1may easily perceive the electronic device40.

The controller190may adjust the transmittance of the shutter unit140using various methods, for example, a method of adjusting a level of driving voltage applied to the shutter unit140and a method of adjusting a duty width of driving voltage applied to the shutter unit140.

In a method of adjusting the level of the driving voltage applied to the shutter unit140, the shutter unit140includes the liquid crystal shutter glass. Transmittance of liquid crystals increases as a higher voltage is applied to the liquid crystals. Thus, the transmittance of the shutter unit140may increase when the level of the driving voltage is raised, while the transmittance of the shutter unit140may decrease when the level the driving voltage is reduced.

In a method of adjusting a duty width of the driving voltage applied to the shutter unit140, defining time for which the liquid crystals are on based on voltage as duty, a longer duty width indicates a longer time the shutter unit140is open. A longer open time of the shutter unit140indicates a longer time light passes through the liquid crystals. Thus, the transmittance of the shutter unit140may increase with a longer duty width of the driving voltage, while the transmittance of the shutter unit140may decrease with a shorter duty width of the driving voltage.

Accordingly, the transmittance of the shutter unit140may be adjusted.

A process of pairing the display apparatus1with the electronic device40is described with reference toFIG. 7.

FIG. 7illustrates an exemplary process of pairing the display apparatus1with an electronic device40.

As illustrated inFIG. 7, when the camera210detects the electronic device40(S200), the controller190analyzes a shape of the electronic device40taken by the camera210(S210) to determine a model name of the electronic device40(S220). Various techniques and structures may be used to determine a model name of the electronic device40by shape analysis, without being particularly limited.

When various marks, for example, a bar code or a quick response (QR) code, to identify a model of the electronic device40are recognized from an image of the electronic device40taken by the camera210, the controller190may determine the model name of the electronic device40based on a corresponding mark.

The controller190acquires a pairing code corresponding to the determined model name (S230), thereby pairing the electronic device40with the display apparatus1. Pairing may be defined as a control operation of functionally combining the display apparatus1and the electronic device40so that both devices operate in synchronization or association. For example, when the display apparatus1and the electronic device40are paired, the display apparatus1may transmit a control signal ordering an operation of the electronic device40to the electronic device40so as to control the operation of the electronic device40.

The controller190may use various methods to acquire the pairing code corresponding to the determined model name. For example, when a relational table of a model name and a pairing code is stored in the storage unit170, the controller190accesses the relational table in the storage unit170to acquire a pairing code corresponding to a model name.

Alternatively, the controller190accesses an external server (not illustrated) through the communication unit150and transmits the determined model name to the server. The controller190may receive the pairing code corresponding to the model name from the server, thereby acquiring the pairing code.

When the display apparatus1and the electronic device40are paired through acquisition of the pairing code, it is possible to control an operation of the electronic device40through the display apparatus1.

When the user inputs a predetermined command through the user input unit160, the controller190transmits a control signal corresponding to the command to the electronic device40so that the operation of the electronic device40is controlled by the command. Accordingly, the electronic device40performs an operation corresponding to the received control signal.

When a voice instruction of the user is detected by the microphone220, the controller190transmits a control signal corresponding to the voice instruction to the electronic device40so that the operation of the electronic device40is controlled by the voice instruction.

While analyzing the shape of the electronic device40to determine the model name of the electronic device40taken by the camera, the controller190may also analyze arrangements and relevant functions of various types of user input interfaces installed in the electronic device40.

A user input interfaces is an input interface installed in the electronic device40for a user's input or manipulation and may be configured as various types, such as a key, a touch pad, and a touch screen.

An arrangement of a user input interface is information on where the user input interface is disposed in the electronic device40taken by the camera210. A relevant function of a user input interface is information on an operation or function performed by the electronic device40when the user manipulates the user input interface.

As illustrated inFIG. 6, the controller190determines information on a type and a model name of the electronic device40through shape analysis of the electronic device40. The controller190determines arrangements and relevant functions of user input interfaces41,42,43,44, and45installed in the electronic device40based on the determined information. For example, the controller190may determine that the electronic device40is a set-top box and the user input interfaces41,42,43,44, and45includes a power on/off button41, a channel up button42, a channel down button43, a volume up button44, and a volume down button45.

When the camera210detects and monitors the electronic device40and the controller190determines the model name of the electronic device40and the user input interfaces41,42,43,44, and45, an action or motion800may occur by the user as illustrated inFIG. 8.

FIG. 8illustrates a screen320when a motion800occurs by a user while the camera210detects the electronic device40.

As illustrated inFIG. 8, a motion800of the user, for example, the user moving a fingertip or touching an interface with a fingertip, may be detected by the camera210. The controller190may determine whether the motion800is made on the user input interfaces41,42,43,44, and45of the electronic device40. The controller190generates a control signal corresponding to a function of a user input interface41,42,43,44, or45on which the motion800is made and transmits the control signal to the electronic device40.

For example,FIG. 8illustrates the motion800is made on the power on/off button41among the user input interface41,42,43,44, and45. Accordingly, the controller190generates a control signal ordering a power on/off operation corresponding to a function of the power on/off button41and transmits the control signal to the electronic device40.

The electronic device40receives the control signal and performs a power on/off operation in the same manner as when the user clicks the power on/off button41.

When the motion800of the user is made on the volume up button44, the controller190transmits a control signal ordering a volume up operation to the electronic device40so that the electronic device40performs the volume up operation corresponding to a function of the volume up button44.

According to this process, the user wearing the display apparatus1may easily control the operation of the electronic device40.