U.S. patent application number 15/403012 was filed with the patent office on 2018-07-12 for powering down of head mounted display based on magnetic sensor detection.
The applicant listed for this patent is Oculus VR, LLC. Invention is credited to Nirav Rajendra Patel.
Application Number | 20180197500 15/403012 |
Document ID | / |
Family ID | 62749590 |
Filed Date | 2018-07-12 |
United States Patent
Application |
20180197500 |
Kind Code |
A1 |
Patel; Nirav Rajendra |
July 12, 2018 |
POWERING DOWN OF HEAD MOUNTED DISPLAY BASED ON MAGNETIC SENSOR
DETECTION
Abstract
A head mounted display (HMD) includes a magnetic sensor to
produce a sensor signal responsive to detecting a magnet within a
first threshold distance. The HMD also includes a circuit
operatively coupled to the magnetic sensor. The circuit determines
that the HMD is to be placed in a storage mode responsive to
receiving the sensor signal from the magnetic sensor. The circuit
powers down components of the HMD responsive to determining that
the HMD is to be placed in the storage mode.
Inventors: |
Patel; Nirav Rajendra; (San
Francisco, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Oculus VR, LLC |
Menlo Park |
CA |
US |
|
|
Family ID: |
62749590 |
Appl. No.: |
15/403012 |
Filed: |
January 10, 2017 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B65D 85/54 20130101;
G09G 2330/026 20130101; G01B 7/14 20130101; G06F 3/147 20130101;
G09G 5/003 20130101; G09G 2330/027 20130101 |
International
Class: |
G09G 5/00 20060101
G09G005/00; B65D 25/02 20060101 B65D025/02; B65D 43/02 20060101
B65D043/02; G01B 7/14 20060101 G01B007/14 |
Claims
1. A head mounted display (HMD) comprising: a magnetic sensor
configured to produce a sensor signal responsive to detecting a
magnet within a first threshold distance; and a circuit operatively
coupled to the magnetic sensor, the circuit configured to determine
that the HMD is to be placed in a storage mode responsive to
receiving the sensor signal from the magnetic sensor and power down
one or more components of the HMD responsive to determining that
the HMD is to be placed in the storage mode.
2. The HMD of claim 1, wherein the magnetic sensor is a Hall Effect
sensor, a fluxgate magnetometer, or a magnetoresistance sensor.
3. The HMD of claim 1, further comprising a proximity sensor
configured to produce a proximity signal responsive to detecting an
object within a second threshold distance, wherein the circuit is
operatively coupled to the proximity sensor to receive the
proximity signal, the circuit further configured to power on the
one or more components responsive to receiving the proximity signal
but not the sensor signal.
4. The HMD of claim 1, further comprising a strap with the magnet,
the strap configured to secure the HMD to a user's head when the
HMD is being used.
5. The HMD of claim 1, wherein the magnet is included in a storage
case for storing the HMD.
6. The HMD of claim 1, further comprising at least another magnetic
sensor at a location different from the magnetic sensor, the
circuit configured to determine whether the HMD is to be placed in
the storage mode based on sensor signals from at least the other
magnetic sensor.
7. A storage case for storing a head mounted display (HMD), the
storage case comprising: enclosing walls defining space to receive
the HMD for storage; and a magnet attached to or embedded in the
enclosing walls at a location so that a magnetic sensor of the HMD
is within a threshold distance when the HMD is stored in the space,
a circuit of the HMD powering down one or more components in the
HMD responsive to the magnetic sensor detecting the magnet within
the threshold distance.
8. The storage case of claim 7, wherein the enclosing walls include
four side walls, a floor and a lid, and wherein the magnet is
attached to or embedded in one of the four side walls, the floor,
or the lid.
9. A method, comprising: producing a sensor signal, by a magnetic
sensor, responsive to detecting a magnet within a first threshold
distance; and responsive to receiving the sensor signal from the
magnetic sensor by a circuit operatively coupled to the magnetic
sensor, determining whether a head mounted display (HMD) is to be
placed in a storage mode; and responsive to determining that the
HMD is to be placed in the storage mode, powering down one or more
components of the HMD.
10. The method of claim 9, wherein the magnetic sensor is a Hall
Effect sensor, a fluxgate magnetometer, or a magnetoresistance
sensor.
11. The method of claim 9, further comprising: producing a
proximity signal, by a proximity sensor, responsive to detecting an
object within a second threshold distance, wherein the circuit is
operatively coupled to the proximity sensor to receive the
proximity signal; and responsive to receiving the proximity signal
but not the sensor signal, powering on the one or more
components.
12. The method of claim 9, further comprising securing, by a strap
with the magnet, the HMD to a user's head when the HMD is being
used.
13. The method of claim 9, wherein the magnet is included in a
storage case for storing the HMD.
14. The method of claim 9, further comprising: determining whether
the HMD is to be placed in the storage mode, by the circuit, based
on sensor signals from at least another magnetic sensor at a
location different from the magnetic sensor.
Description
BACKGROUND
Field of the Disclosure
[0001] The present disclosure generally relates to a head mounted
display, and specifically to powering down of such head mounted
display based on magnetic sensor detection.
Description of the Related Arts
[0002] Virtual reality (VR) systems typically include electronic
display panels that present virtual reality images. For example a
VR system may include a head mounted display (HMD) that includes an
electronic display panel to present VR images to a user. An HMD may
include a proximity sensor that detects when the user has put the
HMD on. Once the proximity sensor senses that the user has worn the
HMD, the electronic display panel turns on. On the other hand, if
the proximity sensor senses that the user has taken off the HMD,
the electronic display panel is turned off to conserve energy.
[0003] HMDs may be stored in cases when not in use. Alternatively,
an HMD may include a strap that is worn by a user to secure the HMD
on the user's head. When the HMD is not in use, the strap may be
packed into an opening on the HMD's housing or wrapped around the
HMD. However, the proximity sensor may detect objects such as the
case or strap approaching the HMD when the HMD is not in use,
thereby causing the electronic display panel to turn on and consume
power unnecessarily.
SUMMARY
[0004] Embodiments relate to powering down an HMD by using a
magnetic sensor of the HMD. The magnetic sensor detects a magnet
that may be located in a storage case or a strap of the HMD. When
the magnetic sensor detects placing of the HMD in the storage case
or folding of the strap based on the proximity of the magnet, the
HMD is powered down,
[0005] In one embodiment, the HMD includes a magnetic sensor to
produce a sensor signal responsive to detecting a magnet within a
first threshold distance. The HMD includes a circuit operatively
coupled to the magnetic sensor. The circuit determines that the HMD
is to be placed in a storage mode responsive to receiving the
sensor signal from the magnetic sensor and powers down components
of the HMD responsive to determining that the HMD is to be placed
in the storage mode.
[0006] In one embodiment, the magnetic sensor is a Hall Effect
sensor, a fluxgate magnetometer, or a magnetoresistance sensor.
[0007] In one embodiment, the HMD includes a proximity sensor to
produce a proximity signal responsive to detecting an object within
a second threshold distance. The circuit is operatively coupled to
the proximity sensor to receive the proximity signal. The circuit
powers on the components responsive to receiving the proximity
signal but not the sensor signal.
[0008] In one embodiment, the HMD includes a strap with the magnet.
The strap secures the HMD to a user's head when the HMD is being
used.
[0009] In one embodiment, the magnet is included in a storage case
for storing the HMD.
[0010] In one embodiment, the HMD includes at least another
magnetic sensor at a location different from the magnetic sensor.
The circuit determines whether the HMD is to be placed in the
storage mode based on sensor signals from at least the other
magnetic sensor.
[0011] In one embodiment, a storage case for storing the HMD
includes enclosing walls defining space to receive the HMD for
storage. The storage case includes a magnet attached to or embedded
in the enclosing walls at a location so that a magnetic sensor of
the HMD is within a threshold distance when the HMD is stored in
the space. A circuit of the HMD powers down components in the HMD
responsive to the magnetic sensor detecting the magnet within the
threshold distance.
[0012] In one embodiment, the enclosing walls of the storage case
include four side walls, a floor and a removable lid. The magnet is
attached to or embedded in one of the four side walls, the floor,
or the lid.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The teachings of the embodiments can be readily understood
by considering the following detailed description in conjunction
with the accompanying drawings.
[0014] FIG. 1 is an example schematic perspective view of an HMD
and a storage case, in accordance with an embodiment.
[0015] FIG. 2 is an example schematic perspective view of an HMD
having a strap with a magnetic sensor, in accordance with an
embodiment.
[0016] FIG. 3 is an example schematic block diagram of an HMD, in
accordance with an embodiment.
[0017] FIG. 4 is a flowchart illustrating an example process for
powering down an HMD, in accordance with an embodiment.
[0018] The figures depict various embodiments for purposes of
illustration only.
DETAILED DESCRIPTION
[0019] In the following description of embodiments, numerous
specific details are set forth in order to provide more thorough
understanding. However, note that the embodiments may be practiced
without one or more of these specific details. In other instances,
well-known features have not been described in detail to avoid
unnecessarily complicating the description.
[0020] Embodiments are described herein with reference to the
figures where like reference numbers indicate identical or
functionally similar elements. Also in the figures, the left most
digits of each reference number corresponds to the figure in which
the reference number is first used.
[0021] Embodiments relate to an HMD having magnetic sensors to
detect when the HMD is not in use and powering down the HMD when
the HMD is not in use. When not in use, the HMD may be packed in a
storage case, or a strap attached to a housing of the HMD may be
collapsed into the HMD for storage. The magnetic sensor detects a
magnet located in the storage case or on the strap and produces a
sensor signal responsive to detecting the magnet. When the magnetic
sensor detects the magnet in its proximity, the HMD powers down to
reduce power consumption.
Example Schematic Perspective View of HMD and Storage Case
[0022] FIG. 1 is an example schematic perspective view of an HMD
100 and a storage case 106 for storing the HMD 100, in accordance
with an embodiment. VR systems typically include user interface
devices such as the HMD 100 to communicate with a controller or a
computing device. The HMD 100 is a display device, worn on a user's
head or as part of a helmet that has an electronic display panel in
front of the user's eyes to display computer-generated imagery
(CGI) or live imagery from the physical world. The electronic
display panel is attached to a housing of the HMD 100.
[0023] The HMD 100 includes a proximity sensor 102 located on or
within the housing of the HMD 100. The proximity sensor 102
produces a proximity signal responsive to detecting an object, such
as the user's head, located within a threshold distance from the
proximity sensor 102. The proximity sensor 102 detects when a user
has put the HMD 100 on to power on the electronic display panel.
The proximity sensor may be a capacitive sensor, a photoelectric
sensor, an inductive proximity sensor, etc.
[0024] The HMD 100 may be stored in the storage case 106 along with
accessories such as headphones, gaming controllers, cameras, etc.
If a user places the HMD 100 in the storage case 106, the proximity
sensor 102 may detect the surface of the storage case 106. As a
result of such detection, the HMD 100 may falsely detect that the
user is currently using the HMD 100, and hence, turn on components
of the HMD 100 (e.g., display panel). Such unnecessary powering on
of the HMD may lead to waste of power.
[0025] To alleviate or prevent waste of power in such
circumstances, a magnetic sensor 104 is provided in the HMD 100.
The magnetic sensor 104 produces a sensor signal responsive to
detecting a magnet 108 located on or within the storage case 106
when a distance 110 between the magnetic sensor 104 and the magnet
108 is less than a threshold distance d. The magnet 108 is located
in the storage case 106 such that the distance between the storage
case 106 and the HMD 100 is less than the threshold distance d when
the HMD 100 is placed within the case 106. In this way, unnecessary
power consumption, heat generation, and battery drainage for the
HMD 100 is reduced or prevented when placed in the storage case 106
for storage.
[0026] The storage case 106 for storing the HMD 100 includes
enclosing walls, e.g., 112a, defining space to receive the HMD 100
for storage as illustrated in FIG. 1. The enclosing walls may be
made of materials such as impact-resistant plastic with internal
foam cushioning to protect the HMD 100 from impacts and drops. The
storage case 106 includes the magnet 108 attached to or embedded in
the enclosing walls at a location so that the magnetic sensor 104
of the HMD 100 is within the threshold distance d when the HMD 100
is stored in the space. The enclosing walls of the storage case 106
include four side walls 112 (112a, 112b, 112c, and 112d), a floor
114, and a removable lid 116. The magnet 108 is attached to or
embedded in one of the four side walls 112, the floor 114, or the
lid 116 of the storage case. In FIG. 1, the lid 116 is shown
removed from the storage case 106. When the HMD 100 is stored in
the storage case 106, the lid may be placed or secured on top of
the storage case 106 to close the storage case 106.
[0027] The magnetic sensor 104 may be a Hall Effect sensor. A Hall
Effect sensor is a linear transducer that varies its voltage output
in response to sensing a magnetic field. The distance 110 from the
Hall Effect sensor 104 to the magnet 108 may be determined from a
voltage output signal of the Hall Effect sensor 104. The magnetic
sensor 104 may be a fluxgate magnetometer. A fluxgate magnetometer
is made of a magnetically susceptible core wrapped by two coils of
wire. When the fluxgate magnetometer 104 is located near the magnet
108 and exposed to its magnetic field, a current in an output coil
of the fluxgate magnetometer 104 may be integrated to yield a
voltage output signal indicating the distance 110 from the fluxgate
magnetometer 104 to the magnet 108. The magnetic sensor 104 may be
a magnetoresistance sensor that changes the value of its electrical
resistance in an externally-applied magnetic field. The change in
resistance of the magnetoresistance sensor 104 may be measured as a
voltage output signal indicating the distance 110 from the
magnetoresistance sensor 104 to the magnet 108.
[0028] When the distance 110 between the magnetic sensor 104 and
the magnet 108 is less than the threshold distance d, meaning the
magnetic sensor 104 senses that the HMD 100 has been placed in the
case 106, the magnetic sensor 104 produces the sensor signal
responsive to detecting the magnet 108. The signal may be a voltage
output as described above. Alternatively, the magnetic sensor 104
may produce a sensor signal in the form of an electric current
using an op-amp to convert the voltage output to the electric
current signal.
[0029] The HMD 100 includes an electric circuit operatively coupled
to the magnetic sensor 104 and connected to components of the HMD
100 (e.g., the electronic display panel). The electric circuit
receives from the magnetic sensor 104 the sensor signal indicating
whether the magnet 108 is located within the threshold distance d
from the magnetic sensor 104, determines that the HMD 100 is to be
placed in a storage mode responsive to receiving the sensor signal
from the magnetic sensor 104 and powers down the components of the
HMD 100 responsive to determining that the HMD 100 is to be placed
in the storage mode, as described below in detail with reference to
FIG. 3. The circuit is also operatively coupled to the proximity
sensor 102 to receive the proximity signal. The circuit powers on
the components of the HMD 100 responsive to receiving the proximity
signal but not the sensor signal.
[0030] In some embodiments, the HMD 100 may include more than one
magnetic sensor and the storage case 106 may include more than one
magnet. The HMD 100 may include at least another magnetic sensor at
a location different from the magnetic sensor 104. The circuit
determines whether the HMD 100 is to be placed in the storage mode
based on sensor signals from at least the other magnetic
sensor.
Example Strap of Head Mounted Display with Magnet
[0031] FIG. 2 is an example schematic perspective view of an HMD
100 having a strap 206, in accordance with an embodiment. The strap
206 is attached to a housing 200 of the HMD 100. The strap 206 may
be worn by a user to secure the HMD 100 on the user's head. The
strap 206 shown in FIG. 2 may include a flexible segment made of a
stretchable band and a semi-rigid segment to conform to a portion
of the user's head. When not in use, the strap 206 may be rolled
up, bunched up, or otherwise collapsed into an opening in the HMD
100. When not in use, the strap 206 may also be wrapped around the
HMD 100 for storage.
[0032] The HMD 100 shown in FIG. 2 includes a proximity sensor 102,
as described in detail above with reference to FIG. 1. The
proximity sensor 102 is located on or within the housing 200 of the
HMD 100 and detects when a user has put the HMD 100 on to
automatically power on the electronic display panel. However, the
proximity sensor 102 may falsely detect that the HMD 100 is in use
when the strap 206 is rolled up, bunched up or otherwise collapsed
into the opening in the HMD 100, or wrapped around the HMD 100,
thereby causing the HMD 100 to turn on its components
unnecessarily.
[0033] The HMD 100 in FIG. 2 also includes a magnetic sensor 104
located on or within the housing 200 of the HMD 100, as described
above with reference to FIG. 1. The magnetic sensor 104 of FIG. 2
functions in the same way as the magnetic sensor 104 of FIG. 1
except that the magnetic sensor 104 of FIG. 2 detects the magnet
208 in the strap 206.
Example Sensors and Circuit for Power Down Operation
[0034] FIG. 3 is an example schematic block diagram of the HMD 100
interacting with a magnet 308, in accordance with an embodiment.
The HMD 100 may include, among other components, a proximity sensor
102, a magnetic sensor 104, an electric circuit 304, a central
processing unit (CPU) 312, a memory 314, and other components 316
(e.g., a display panel). The proximity sensor 102 is located on or
within a housing of the HMD 100 to detect when a user has put the
HMD 100 on. When the proximity sensor 102 detects that the user has
put the HMD 100 on, it produces a proximity signal 306. The circuit
304 is operatively coupled to the proximity sensor 102 to receive
the proximity signal 306. The circuit 304 powers on the components
316 of the HMD 100 responsive to receiving the proximity signal
306.
[0035] The magnet 308 shown in FIG. 3 may be located on or within
the case 106 or the strap 206, as described in detail above with
reference to FIGS. 1 and 2. The distance 310 is the distance
between the magnet 308 and the magnetic sensor 104 in the HMD 100.
The magnetic sensor 104 in the HMD 100 is configured to detect the
magnet 308 when the distance 310 between the magnet 308 and the
magnetic sensor 104 is less than a threshold distance d, and
produce a sensor signal 302 responsive to detecting the magnet 308.
The magnetic sensor 104 may be a Hall Effect sensor, a fluxgate
magnetometer, or a magnetoresistance sensor, as described above in
detail with reference to FIG. 1.
[0036] When the magnetic sensor 104 in the HMD 100 detects the
magnet 308 located less than a threshold distance d from the
magnetic sensor 104, it sends the sensor signal 302 to an electric
circuit 304. The sensor signal may be an electric current or a
voltage V. The electric circuit 304 is located within the housing
of the HMD 100 and electrically connected to the components 316 by
the bus 300. The electric circuit 304 receives the sensor signal
302 from the magnetic sensor 104, determines that the HMD 100 is to
be placed in a storage mode responsive to receiving the sensor
signal 302 from the magnetic sensor 104 and powers down the
components 316 of the HMD 100 responsive to determining that the
HMD 100 is to be placed in the storage mode. The electric circuit
304 may include a switch comparator op-amp to compare the voltage V
signal 302 from the magnetic sensor 104 with a threshold voltage
V.sub.T. In embodiments, the electric circuit 304 receives the
voltage V signal 302 from the magnetic sensor 104, and powers down
the components 316 if the voltage V exceeds the threshold voltage
V.sub.T.
[0037] In embodiments, the electric circuit 304 may receive the
sensor signal 302 from the magnetic sensor 104 in the form of an
electric current. The electric circuit 304 may convert the electric
current to a voltage by a sense resistor. The electric circuit 304
may further include a switch comparator op-amp to power down the
components 316 if the voltage exceeds the threshold voltage
V.sub.T. In embodiments, the electric circuit 304 may receive the
sensor signal 302 from the magnetic sensor 104 and communicate with
the CPU 312 and memory 314 via the bus 300. The CPU 312 may power
down the components 316 responsive to communicating with the
circuit 304.
Example Process for Powering Down Electronic Display Panel
[0038] FIG. 4 is a flowchart illustrating an example process for
powering down components 316 of an HMD 100, in accordance with an
embodiment. In some embodiments, the process may have different
and/or additional steps than those described in conjunction with
FIG. 4. Steps of the process may be performed in different orders
than the order described in conjunction with FIG. 4. Some steps may
be executed in parallel. Alternatively, some of the steps may be
executed in parallel and some steps executed sequentially.
Alternatively, some steps may execute in a pipelined fashion such
that execution of a step is started before the execution of a
previous step.
[0039] An HMD 100 having a magnetic sensor 104 located on or within
a housing of the HMD 100 is placed 400 within a storage case 106.
The magnetic sensor 104 detects 404 a magnet 108 in the storage
case 106 located within a threshold distance d from the magnetic
sensor 104. The magnetic sensor produces 408 a sensor signal 302 in
the form of an output voltage or current, responsive to detecting
the magnet 108 within the threshold distance d.
[0040] An electric circuit 304, operatively coupled to the magnetic
sensor 104, receives 412 the sensor signal 302 from the magnetic
sensor 104. The electric circuit 304, which may include a switch
comparator, determines that the HMD 100 is to be placed in a
storage mode responsive to receiving the sensor signal 302 from the
magnetic sensor 104 and powers down the components 316 of the HMD
100 responsive to determining that the HMD 100 is to be placed in
the storage mode.
[0041] The foregoing description of the embodiments has been
presented for the purpose of illustration; it is not intended to be
exhaustive or to limit the embodiments to the precise forms
disclosed. Persons skilled in the relevant art can appreciate that
many modifications and variations are possible in light of the
above disclosure.
[0042] Finally, the language used in the specification has been
principally selected for readability and instructional purposes,
and it may not have been selected to delineate or circumscribe the
inventive subject matter. It is therefore intended that the scope
be limited not by this detailed description, but rather by any
claims that issue on an application based hereon. Accordingly, the
disclosure of the embodiments is intended to be illustrative, but
not limiting, of the scope, which is set forth in the following
claims.
* * * * *