KR20150009731A - Smart device attached laser pointer and distance/length measurement method using it - Google Patents

Abstract

The present invention provides a smart device with an attached laser pointer, which can measure a distance by using a laser pointer, and can measure the distance from the smart device to a subject by using a camera mounted in the smart device and the laser pointer. The smart device with an attached laser pointer according to a first invention of the present application is a smart device, which comprises a camera module mounted in the smart device, and including a camera lens and an image sensor converting the light introduced through the camera lens into an electrical signal; a display unit for displaying the image; an input unit for receiving the input information from a user; a control unit for calculating the distance from the laser pointer to a subject which the laser light reaches by using the size of the image reflected from the image sensor; and the laser pointer combined with an interface of the smart device so as to transmit laser light in the front direction or the rear direction of the smart device by using a laser diode arranged in a predetermined position.

Description

TECHNICAL FIELD [0001] The present invention relates to a smart device with a laser pointer and a distance / length measuring method using the smart device.

TECHNICAL FIELD The present invention relates to a technique for measuring a distance to an object using a smart device and a technique for measuring a distance from the smart device to the object and a length of the object using a camera and a laser pointer built in the smart device .

In general, the distance measuring device uses ultrasonic, infrared, or laser.

The ultrasonic distance measuring device emits ultrasonic waves, senses ultrasonic waves reflected from the object, and converts the time difference from the dispatched time to the sensed time into a distance. The infrared range finder emits infrared light and measures the reflected light to calculate the distance. The laser distance measuring apparatus includes a laser transmitting unit for emitting laser light and a laser receiving unit for receiving the laser light reflected on the target. When the user fires the laser light on the target to measure the distance, And then calculates and displays the distance from this time.

However, since these products are stand-alone products, they must be equipped with batteries at all times because they operate as batteries, and they are inconvenient to carry and have a high price because of their large size.

Recently, there has been proposed a technique for measuring a distance to a subject and displaying the distance therebetween.

A portable terminal disclosed in Japanese Patent Application No. 10-774105 (published on November 6, 2007) includes a camera module including a lens, an image sensor for converting light incident from the lens into an electric signal, a display unit An input unit for inputting information or selecting a function desired by the user, a laser transmitting / receiving unit for emitting a laser beam and receiving laser light reflected on the subject, and a display unit for displaying a video signal read from the camera module The time from when the laser beam is emitted by the laser transmitting and receiving unit to the time when the laser beam is reflected to the object and reaches the laser transmitting and receiving unit is measured and the distance from the measured time to the object is calculated, On the display unit.

However, in addition to the transmitter for emitting the laser beam, the portable terminal includes a receiver for receiving reflected laser light, a lens for distance measurement, a plurality of mirrors, a time measuring unit, and the like, can not do it.

Accordingly, the present invention provides a smart device with a laser pointer attached thereto which can measure a distance using a laser pointer, and a distance / length measurement method using the same.

In addition, the present invention provides a smart device with a laser pointer attached thereto which can measure the distance from a smart device to a subject using a camera and a laser pointer built in the smart device, and a distance / length measurement method using the smart device.

In addition, the present invention provides a smart device with a laser pointer capable of measuring the length of a subject using a camera built in the smart device and a plurality of laser diodes, and a distance / length measuring method using the smart device.

A smart device to which a laser pointer according to the first aspect of the present invention is attached is a smart device to which a laser pointer is attached. The smart device includes a camera lens mounted on the smart device, and converts the light incident through the camera lens into an electrical signal A camera module including an image sensor; A display unit for displaying an image; An input unit for receiving information from a user; A controller for calculating a distance from the laser pointer to a subject to which the laser beam reaches using an image size projected on the image sensor; And a laser pointer coupled to the interface of the smart device to transmit laser light in the front or back direction of the smart device using a laser diode disposed at a predetermined location.

Preferably, the image processing apparatus further includes a storage unit that stores a relationship table between a size (hx, number of pixels) of the image projected onto the image sensor and a distance (dx) from the laser pointer to a subject to which the laser light reaches.

Preferably, if the size (hx, number of pixels) of the image projected onto the image sensor is between the sizes of the two neighboring images on the relationship table, the control unit calculates the laser light from the laser pointer (Dx) of the object to be reached.

(Equation)

Here, h1 and h2 are the sizes of neighboring images, and d1 and d2 are the distances from the laser pointer corresponding to h1 and h2 to the subject

Preferably, the control unit calculates a distance d from the laser pointer to a subject to which the laser light arrives, using the following equation.

(Equation)

Here, s is the distance from the center of the camera lens to the light source, and [theta] is an angle between the distance (l) from the center of the camera lens to the light formed on the subject and the distance (d) between the light source and the subject.

Preferably, the interface of the smart device is a USB connection interface or the interface of the smart device is an earphone connection interface.

According to a second aspect of the present invention, there is provided a smart device to which a laser pointer is attached, the smart device having a laser pointer attached thereto, the smart device comprising: a camera lens mounted on the smart device; A camera module including an image sensor for converting the image signal into an image signal; A display unit for displaying an image; An input unit for receiving information from a user; A controller for calculating a distance and a size from the laser pointer to a subject to which the laser beam reaches using an image size projected on the image sensor; And a laser pointer coupled to the interface of the smart device to measure the distance of the subject by emitting laser light at two visually recognizable locations.

Preferably, the laser pointer comprises: a laser diode disposed at a predetermined position; And a filter cut in a straight line or a cross shape in front of the laser diode.

Preferably, the laser pointer comprises: a central laser diode disposed at a predetermined position; And at least one laser diode for measuring a subject size arranged to form a predetermined angle with a central axis of the central laser diode.

Preferably, the image processing apparatus further includes a storage unit that stores a relationship table between a size (hx, number of pixels) of the image projected onto the image sensor and a distance (dx) from the laser pointer to a subject to which the laser light reaches.

Preferably, laser beams emitted from the central laser diode of the laser pointer and the laser diode for measuring the subject size are collimated so as to illuminate one end and the other end of the subject, respectively, and the size of the image (hx, Is present between the sizes of two adjacent images on the relationship table, the control unit calculates a distance dx from the laser pointer to a subject to which the laser light reaches, using the following equation.

(Equation)

Here, h1 and h2 are the sizes of neighboring images, and d1 and d2 are distances from the laser pointer corresponding to h1 and h2 to the object.

Preferably, the control unit calculates the length Lx of the subject using the distance dx to the subject and the following equation.

(Equation)

Alpha is an angle between the optical axis of the laser beam emitted from the center laser diode and the optical axis of the laser beam emitted from the laser diode for measuring the object size.

Preferably, the control unit calculates a distance d from the laser pointer to a subject to which the laser light arrives and a length L of the subject using Equations (1) and (2) below.

(1)

Here, s is the distance from the center of the camera lens to the light source, and [theta] is an angle between the distance (l) from the center of the camera lens to the light formed on the subject and the distance (d) between the light source and the subject.

(2)

Alpha is an angle between the optical axis of the laser beam emitted from the center laser diode and the optical axis of the laser beam emitted from the laser diode for measuring the object size.

According to a third aspect of the present invention, there is provided a method for measuring a distance of a smart device to which a laser pointer is attached, the method comprising: a laser light reaching a subject from a laser pointer attached to the smart device; Projecting an image of a subject to an image sensor in a camera module built in the smart device; And calculating a distance from the laser pointer to a subject to which the laser light arrives by using an image size projected on the image sensor.

Preferably, the step of calculating the distance uses the following equation.

(Equation)

Here, s is the distance between the center of the camera lens in the camera module and the light source, and? Is an angle between the distance l from the center of the camera lens to the light formed on the subject and the distance d between the light source and the subject.

Preferably, the step of calculating the distance stores a table of the relationship between the size (hx, number of pixels) of the image projected on the image sensor and the distance (dx) from the laser pointer to the object to which the laser light reaches Storing; And when the size (hx, number of pixels) of the image projected on the image sensor is between the sizes of two adjacent images on the relationship table, the following equation is used to determine the distance from the laser pointer to the object And calculating the distance dx.

(Equation)

Here, h1 and h2 are the sizes of neighboring images, and d1 and d2 are distances from the laser pointer corresponding to h1 and h2 to the object.

According to a fourth aspect of the present invention, there is provided a method of measuring a subject length of a smart device having a laser pointer attached thereto, the method comprising: a plurality of laser beams reaching a predetermined position of a subject from a laser pointer attached to the smart device; Projecting an image of a subject to an image sensor in a camera module built in the smart device; Calculating a distance from the laser pointer to a subject to which the laser beam reaches using an image size projected on the image sensor; And calculating the length of the subject using the length up to the subject and the angle of the plurality of laser beams.

Preferably, the step of calculating the distance is characterized by using the following equation.

(Equation)

Here, s is the distance between the center of the camera lens in the camera module and the light source, and? Is an angle between the distance l from the center of the camera lens to the light formed on the subject and the distance d between the light source and the subject.

Preferably, the step of calculating the distance stores a relationship table between a size (h, number of pixels) of the image projected onto the image sensor and a distance (d) from the laser pointer to a subject to which the laser light reaches Storing; And when the size h of the image projected on the image sensor is between the sizes of two neighboring images on the relationship table, the distance d from the laser pointer to the object to which the laser light reaches, ). ≪ / RTI >

(Equation)

Here, h1 and h2 are the sizes of neighboring images, and d1 and d2 are distances from the laser pointer corresponding to h1 and h2 to the object.

Preferably, the step of calculating the length of the subject is characterized by using the following expression.

(Equation)

Alpha is an angle between the optical axis of the laser beam emitted from the center laser diode and the optical axis of the laser beam emitted from the laser diode for measuring the object size.

According to the present invention, since the distance from the smart device to the subject can be measured using the camera and the laser pointer built in the smart device, and the length of the subject can be measured, the laser light receiver, the distance measuring lens, It is possible to achieve miniaturization and cost reduction of the smart device without the components.

FIG. 1 is a block diagram of a portable terminal for distance measurement according to the related art,
FIG. 2 is a schematic diagram of a smart device capable of distance measurement according to an embodiment of the present invention;
3 is an illustration of a distance measurement method using optical triangulation according to an embodiment of the present invention,
4 is a diagram illustrating a method of measuring a distance according to an automatic focus of a camera according to an exemplary embodiment of the present invention.
FIG. 5 illustrates a laser pointer having a plurality of laser diodes according to another embodiment of the present invention,
6 is a diagram illustrating a method of measuring a subject size using a plurality of laser diodes according to another embodiment of the present invention, and Fig.
7 is a view illustrating an example of a method of measuring a subject size according to another embodiment of the present invention.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, the terms "comprises" or "having" and the like refer to the presence of stated features, integers, steps, operations, elements, components, or combinations thereof, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

Also, the terms " part, "" unit," " module, "and the like, which are described in the specification, refer to a unit for processing at least one function or operation, Software. ≪ / RTI >

In the following description of the present invention with reference to the accompanying drawings, the same components are denoted by the same reference numerals regardless of the reference numerals, and redundant explanations thereof will be omitted. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.

FIG. 2 is a schematic diagram of a smart device capable of distance measurement according to an embodiment of the present invention, which includes a smart device main body 200 and a laser pointer 300 attached to the smart device main body.

The smart device main body 200 includes a camera module 210 mounted on the smart device main body, a control unit 220, a storage unit 230, a power supply unit 240 switch 250 including a battery, (Not shown), and an input unit (not shown) for receiving information from a user.

The camera module 210 mounted on the smart device main body according to an embodiment of the present invention includes a camera lens 211 and an image sensor 213.

The laser pointer 300 according to the present invention can transmit the laser light in the vertical direction to the front or rear surface of the smart device body 200 using the laser diode 310 disposed at a predetermined position. The laser pointer 300 may be attached in the vertical direction through a combination of the USB interface convex portion 320 in the laser pointer 300 and the USB interface concave portion 260 in the smart device body 200 according to an embodiment of the present invention . Also, according to another embodiment of the present invention, the laser pointer 230 may be attached to the smart device body in the vertical direction through the interface for the earphone.

According to an embodiment of the present invention, the laser pointer 300 may further include a push button (not shown), and the laser light may be launched by the smart device user pressing the push button. According to another embodiment of the present invention, a user executes a laser pointer operation application program installed on the smart device body, and laser light can be emitted from the laser pointer 300 through a touch of the touch panel. Here, the application program for operating the laser pointer 300 is self-explanatory to the application program design engineer applicable to the smart device, and does not correspond to the gist of the present invention, so that the essence of the present invention may be obscured, .

3 is a diagram illustrating a distance measurement method using optical triangulation according to an embodiment of the present invention.

When the laser pointer 300 illuminates the subjects O1 and O2, the images of the subjects O1 and O2 are formed on the image sensor 213 via the camera lens 211 in the camera module 210 mounted on the smart device main body . The angle θ between the camera lens 211 and the laser pointer 213 with respect to the subject O1 and O2 increases as the distance d between the subject O1 and O2 to which the laser beam reaches and the laser pointer 300 increases. The refractive angle a that is refracted by the camera lens 211 is also reduced and the size h of the image projected onto the image sensor 213 is also reduced.

More specifically, it is as follows.

An angle? Between the camera lens 211 and the laser pointer 300 with respect to the subject is represented by Equation (1).

Here, s is the distance from the center of the camera lens 211 to the light source 310.

Therefore, the distance d between the subject and the light source 310 is expressed by Equation (2).

Since the distance s from the center of the camera lens 211 to the light source 310 is a fixed value, when the size h of the image projected on the image sensor 213 is measured, (D) between the first and second electrodes 310a and 310b.

According to another embodiment of the present invention, in a smart device having an auto focus function, it is preferable to use information on the distance between the image sensor and the camera lens in a database.

More specifically, the angle h between the light source and the subject (d) between the size h of the image projected onto the image sensor 213, the refraction angle a, the distance l from the center of the camera lens to the light formed on the subject, (h, pixel number) of the image projected on the image sensor 213 is stored in the smart device's internal storage 230, the corresponding relationship between the subject and the distance d between the subject and the light source is stored in the smart- The distance can be calculated by calling the distance d between the subject and the light source.

dx (mm)

hx (pixel) resolution (mm) 1000 0.14889 1600 6.67 2000 0.07486 1450 6.67 3000 0.049958 1300 6.67 4000 0.037482 1150 6.67 5000 0.029991 1000 6.67 6000 0.024995 850 6.67 7000 0.021425 700 6.67 8000 0.018748 550 6.67 9000 0.016665 400 6.67 10000 0.014999 250 6.67 11000 0.013636 100 6.67

Although not shown, according to another embodiment of the present invention, the light source 310 of the laser pointer 300 is disposed not in a direction parallel to the camera lens, but inclined at a predetermined angle upward or downward in a straight direction of the laser light, Light is emitted. According to this, when the subject is located at a long distance, since the image sensor can be used more widely, the accuracy of the distance measurement can be improved. According to this embodiment, instead of using the triangulation method, for example, the subject may be measured every 10 centimeters, the measured data may be stored in a database, and the distance to the subject may be measured using interpolation.

Since the camera module 210 mounted on the smart device has an auto focus function, the camera lens 211 moves back and forth depending on the position of the focus. Here, the auto focus function means a function of automatically adjusting the camera lens back and forth to focus on the subject.

4 is a diagram illustrating a method of measuring a distance according to an automatic focusing of a camera according to an exemplary embodiment of the present invention.

In a smart device having an auto-focus function, the distance d1 between the light source and the subject is exactly the distance to the light source when the camera lens moves backward. On the other hand, when the camera lens moves forward, the distance d2 between the subject and the light source is different by the moving distance dM of the camera lens. However, according to the present invention, the distance (l) from the center of the camera lens to the light formed on the subject and the distance (d) between the light source and the object are not dynamically measured by using the time difference between the launching time and the receiving time of the laser light source, The moving distance dM of the camera lens has no influence on the angle θ and the moving distance dM of the camera lens is a distance d, It is only in millimeters (mm) and can be ignored.

Meanwhile, according to an embodiment of the present invention, when the actual distance is measured using the database shown in Table 1, the distance information dx can be inversely calculated using an interpolation method.

For example, if the size of the image (hx, number of pixels) is 750, a method of reading the section of (h1, d1) = (950, 6000) and (h2, d2) = (700, 7000) .

That is, if the size of the image (hx, number of pixels) is 750, the subject is calculated to be about 6.8 meters from the laser pointer.

When the distance is calculated using the interpolation method, it is desirable to consider the distortion rate of the known camera lens.

According to another embodiment of the present invention, it is preferable that information on the distance between the image sensor and the camera lens is stored in a database for each smart device.

Further, according to the present invention, the size of a subject can be measured using a laser pointer having a plurality of laser diodes.

5 is a laser pointer having a plurality of laser diodes according to another embodiment of the present invention. The laser pointer 300 includes a horizontal laser diode 310 for horizontal measurement, a laser diode 330 for vertical measurement And a diode 340.

The emission angle of the laser diode for horizontal axis measurement 330 maintains a beta angle with the optical axis of the laser light emitted from the center laser diode 310, Alpha] angle with the optical axis of the laser beam emitted from the center of the laser beam.

Here, the alpha and beta angles do not necessarily have to be the same value, and the storage of the smart device stores alpha alpha and beta beta angles.

6 is a diagram illustrating a method of measuring a subject size using a plurality of laser diodes according to another embodiment of the present invention.

When the laser beam emitted from the central laser diode 310 and the longitudinal axis measurement laser diode 340 of the laser pointer 300 respectively aim at the top and bottom of the subject O1, An image is formed on the image sensor 213 via the camera lens 211 in the camera module 210 mounted on the image sensor 213.

First, the control unit 220 calculates the distance d between the object O1 and the laser pointer 300 to which the laser light reaches, using Equation (3). Then, the control unit 220 calculates the height L1 of the subject O1 using Equation (4).

It is obvious to those skilled in the art that the width of a subject can be calculated in the same manner.

Meanwhile, the method of measuring the size of a subject is applied to a smart device having an auto-focus function in a manner similar to that of FIG. 6, and thus will not be described.

7 is a view illustrating an example of a method of measuring a subject size according to another embodiment of the present invention.

A cruciform cross-shaped filter 350 is disposed in front of the central laser diode 310 of the laser pointer 300.

For example, when the center laser diode 310 emits laser light, when the center of the cross-shaped laser light passing through the cross filter 350 and the bottom of the cruciform are aimed at illuminating the upper and lower ends of the subject O1, An image is formed on the image sensor 213 via the camera lens 211 in the camera module 210 mounted on the smart device body. The rest is the same as in FIG. 6, and a detailed description thereof will be omitted.

In the present invention, the term " smart device " does not simply mean a smart phone, but should be understood as a concept that collectively refers to a smart device equipped with a camera module. For example, a smart phone, a tablet PC, a notebook computer, and a general camera with a calculation function.

The embodiments and the accompanying drawings described in the present specification are merely illustrative of some of the technical ideas included in the present invention. Accordingly, the embodiments disclosed herein are for the purpose of describing rather than limiting the technical spirit of the present invention, and it is apparent that the scope of the technical idea of the present invention is not limited by these embodiments. It will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

200: Smart device body
210: camera module
211: camera lens
213: Image sensor
220:
230:
240: Power supply
250: Switch
260: USB interface component
300: laser pointer
310: laser diode (light source)
320: Provision of USB interface

Claims (20)

A smart device to which a laser pointer is attached,
A camera module mounted on the smart device, the camera module including a camera lens and an image sensor for converting light incident through the camera lens into an electrical signal;
A display unit for displaying an image;
An input unit for receiving information from a user;
A controller for calculating a distance from the laser pointer to a subject to which the laser beam reaches using an image size projected on the image sensor; And
A laser pointer coupled to an interface of the smart device to transmit laser light in a front or back direction of the smart device using a laser diode disposed at a predetermined location,
Wherein the laser pointer is attached to the smart device.
The method according to claim 1,
Further comprising a storage unit for storing a table of relationship between a size (hx, number of pixels) of an image projected onto the image sensor and a distance (dx) from a laser pointer to a subject to which the laser light reaches, .
3. The method of claim 2,
If the size (hx, number of pixels) of the image projected onto the image sensor is between the sizes of the two neighboring images on the relationship table, the control unit calculates, from the laser pointer, And a distance dx between the laser pointer and the laser pointer.
(Equation)

Here, h1 and h2 are the sizes of neighboring images, and d1 and d2 are the distances from the laser pointer corresponding to h1 and h2 to the subject
The method according to claim 1,
Wherein the controller is attached with a laser pointer for calculating a distance d from the laser pointer to a subject to which the laser light arrives, using the following equation.
(Equation)

Here, s is the distance from the center of the camera lens to the light source, and [theta] is an angle between the distance (l) from the center of the camera lens to the light formed on the subject and the distance (d) between the light source and the subject.
5. The method according to any one of claims 1 to 4,
The interface of the smart device is a smart device to which a laser pointer, which is a USB connection interface, is attached.
5. The method according to any one of claims 1 to 4,
Wherein the interface of the smart device is an interface for connection to an earphone, to which a laser pointer is attached.
A smart device to which a laser pointer is attached,
A camera module mounted on the smart device, the camera module including a camera lens and an image sensor for converting light incident through the camera lens into an electrical signal;
A display unit for displaying an image;
An input unit for receiving information from a user;
A controller for calculating a distance and a size from the laser pointer to a subject to which the laser beam reaches using an image size projected on the image sensor; And
A laser pointer coupled to an interface of the smart device to measure a distance of a subject by emitting laser light at two visually identifiable locations;
Wherein the laser pointer is attached to the smart device.
8. The laser pointer according to claim 7,
A laser diode disposed at a predetermined position; And
A filter cut in a straight line or a cross shape in front of the laser diode
Wherein the laser pointer is attached to the smart device.
8. The laser pointer according to claim 7,
A center laser diode disposed at a predetermined position; And
At least one object size measuring laser diode arranged to form a predetermined angle with the central axis of the central laser diode
Wherein the laser pointer is attached to the smart device.
10. The method according to claim 8 or 9,
Further comprising a storage unit for storing a table of relationship between a size (hx, number of pixels) of an image projected onto the image sensor and a distance (dx) from a laser pointer to a subject to which the laser light reaches, .
10. The method of claim 9,
(Hx, number of pixels) to be projected onto the image sensor is smaller than a distance between the center laser diode of the laser pointer and the laser beam emitted from the laser diode for measuring the subject size, Wherein the controller is equipped with a laser pointer for calculating a distance dx from the laser pointer to a subject to which the laser light arrives if the distance between two neighboring sizes of the image is between the laser pointer and the object.
(Equation)

Here, h1 and h2 are the sizes of neighboring images, and d1 and d2 are distances from the laser pointer corresponding to h1 and h2 to the object.
12. The method of claim 11,
Wherein the control unit attaches a laser pointer for calculating a distance Lx of a subject using the distance dx to the subject and the following equation.
(Equation)

Alpha is an angle between the optical axis of the laser beam emitted from the center laser diode and the optical axis of the laser beam emitted from the laser diode for measuring the object size.
10. The apparatus according to claim 9,
Wherein a laser pointer is attached to calculate a distance d from the laser pointer to a subject to which the laser light reaches and a length L of the subject using Equation 1 and Equation 2 below.
(1)

Here, s is the distance from the center of the camera lens to the light source, and [theta] is an angle between the distance (l) from the center of the camera lens to the light formed on the subject and the distance (d) between the light source and the subject.
(2)

Alpha is an angle between the optical axis of the laser beam emitted from the center laser diode and the optical axis of the laser beam emitted from the laser diode for measuring the object size.
The laser light reaching the object from the laser pointer attached to the smart device;
Projecting an image of a subject to an image sensor in a camera module built in the smart device; And
Calculating a distance from the laser pointer to a subject to which the laser light reaches using an image size projected on the image sensor
Wherein the distance between the laser pointer and the laser pointer is measured.
15. The method of claim 14, wherein calculating the distance comprises:
Wherein the following formula is used. ≪ RTI ID = 0.0 > 11. < / RTI >
(Equation)

Here, s is the distance between the center of the camera lens in the camera module and the light source, and? Is an angle between the distance l from the center of the camera lens to the light formed on the subject and the distance d between the light source and the subject.

15. The method of claim 14, wherein calculating the distance comprises:
Storing a relationship table between a size (hx, number of pixels) of an image projected onto the image sensor and a distance (dx) from the laser pointer to a subject to which the laser light reaches; And
(Hx, number of pixels) projected onto the image sensor is between the sizes of two neighboring images on the relationship table, a distance from the laser pointer to a subject to which the laser light reaches, (dx)
Wherein the laser pointer is attached to the smart device.
(Equation)

Here, h1 and h2 are the sizes of neighboring images, and d1 and d2 are distances from the laser pointer corresponding to h1 and h2 to the object.
Each of a plurality of laser beams from a laser pointer attached to a smart device reaching a predetermined position of the subject;
Projecting an image of a subject to an image sensor in a camera module built in the smart device;
Calculating a distance from the laser pointer to a subject to which the laser beam reaches using an image size projected on the image sensor; And
Calculating a length of the subject using the length up to the subject and the angle of the plurality of laser lights
Wherein the distance between the laser pointer and the laser pointer is measured.
18. The method of claim 17,
Wherein the step of calculating the distance uses the following equation: < EMI ID = 15.0 >
(Equation)

Here, s is the distance between the center of the camera lens in the camera module and the light source, and? Is an angle between the distance l from the center of the camera lens to the light formed on the subject and the distance d between the light source and the subject.
18. The method of claim 17,
Wherein the calculating the distance comprises:
Storing a relationship table between a size (h, number of pixels) of an image projected onto the image sensor and a distance (d) from a laser pointer to a subject to which the laser light reaches; And
(D) from the laser pointer to a subject to which the laser beam reaches, using the following equation, if the size h of the image projected onto the image sensor is between the sizes of the two neighboring images on the relationship table: ≪ / RTI >
Wherein the laser pointer is attached to the smart device.
(Equation)

Here, h1 and h2 are the sizes of neighboring images, and d1 and d2 are distances from the laser pointer corresponding to h1 and h2 to the object.
20. The method according to claim 18 or 19,
Wherein the step of calculating the length of the subject uses the following formula: < EMI ID = 1.0 >
(Equation)

Alpha is an angle between the optical axis of the laser beam emitted from the center laser diode and the optical axis of the laser beam emitted from the laser diode for measuring the object size.

Images