TWI654475B - Projector - Google Patents

Abstract

A projector comprising a light source, a spatial light modulator, a lens, an infrared receiver, and an arithmetic unit. When the projector starts the ranging function, the light source emits the first light at the first time. The spatial light modulator generates a second light based on the first light. The lens shoots the second light toward the object to be tested at a second time. The object to be tested reflects the second light to form a third light that is directed toward the projector. The wavelengths of the first to third rays are in the infrared wavelength range. The infrared receiver receives the third light at a third time. The computing unit is coupled to the light source and the infrared receiver and obtains the distance between the object to be tested and the projector according to the first time to the third time and the speed of light. When the projector turns off the ranging function, the light source emits visible light for projection and the infrared receiver can receive infrared remote control signals.

Description

Projector

The present invention relates to a projector, and more particularly to a projector having a ranging function and capable of automatically adjusting a projected picture according to geometric features of the projection surface and surface fluctuations.

As technology advances, projectors continue to shrink in size and provide more and more powerful features. In general, the user usually projects the image onto a relatively flat and geometrically curved projection surface (such as a projection screen or wall) through the projector to achieve a better projection effect.

However, due to environmental constraints, it is sometimes difficult for a user to find an ideal object as a projection surface, and it is only possible to select an object having an uneven surface or an irregular shape as a projection surface. Since the conventional projector cannot automatically adjust the projection image according to the geometric features of the projection surface and the surface undulation, the image displayed on the projection surface with uneven surface or irregular shape is prone to distortion or deformation, which needs to be overcome.

In view of this, the present invention proposes a projector to effectively solve the above problems encountered in the prior art.

A projector in accordance with an embodiment of the present invention is a projector. Here In an embodiment, the projector includes a light source, a spatial light modulator, a lens, an infrared receiver, and an arithmetic unit. When the projector starts the ranging function to measure a sample to be tested, the light source emits a first light at a first time, and the wavelength of the first light is in the infrared wavelength range. The spatial light modulator is configured to generate a second light according to the first light, and the wavelength of the second light is in the infrared wavelength range. The lens is used to shoot the second light to the object to be tested at a second time, and the object to be tested reflects the second light to form a third light that is directed to the projector, and the wavelength of the third light is in the infrared wavelength range. The infrared receiver is configured to receive the third light at a third time. The computing unit is coupled to the light source and the infrared receiver, respectively, for obtaining a first distance between the object to be tested and the projector according to the first time, the second time, the third time, and the light speed. Wherein, when the projector turns off the ranging function, the light source can emit a visible light line for projection and the infrared receiver can receive an infrared remote control signal from an infrared remote controller.

In one embodiment, the projector further includes a housing, the light source, the spatial light modulator, and the computing unit are disposed in the housing, and the lens and the infrared receiver are respectively disposed on the housing.

In one embodiment, the lens and the infrared receiver are disposed adjacent to each other on the same side of the housing.

In an embodiment, the operation unit first subtracts the total time length between the first time and the third time by the first time length between the first time and the second time to obtain the second time and the third time. After the second time length, the second time length is multiplied by the speed of light to obtain a first distance between the object to be tested and the projector.

In an embodiment, the object to be tested includes N regions to be tested, N is a positive integer greater than 1, and the second ray corresponds to the first region to be tested in the N regions to be tested and is determined by the first region to be tested. The second light is reflected to form a third light, and the first distance is a distance between the first area to be tested and the projector.

In an embodiment, when the projector starts the ranging function, the light source emits a fourth light at a fourth time and the fifth light, the fourth light, and the fifth light are generated by the spatial light modulator according to the fourth light. The wavelength is in the infrared wavelength range and the fifth light system corresponds to the Kth to-be-measured region of the N to-be-measured regions, and the lens emits the fifth light to the Kth to-be-tested region RK at the fifth time and is waited by the Kth The measuring area reflects the fifth light to form a sixth light that is directed to the projector. When the infrared receiver receives the sixth light at the sixth time, the computing unit obtains the first time according to the fourth time, the fifth time, the sixth time, and the speed of light. K The Kth distance between the area to be tested and the projector, K is a positive integer greater than 1 and less than or equal to N.

In an embodiment, when the computing unit obtains the first distance to the Nth distance between the projector and the first to-be-measured area to the Nth to-be-measured area of the N to be tested, the operation unit is according to the first The distance from the ~Nth distance is obtained from the surface fluctuation of the object to be tested and the projection parameters of the projector are adjusted accordingly, so that the projector can project a picture on the object to be tested according to the adjusted projection parameter, and the picture can respond to the surface fluctuation of the object to be tested. Change without distortion or distortion.

Another embodiment in accordance with the invention is also a projector. In this embodiment, the projector includes a light source, a spatial light modulator, a lens, an infrared receiver, and an arithmetic unit. When the projector starts the ranging function, the object to be measured is In the line ranging, if the object to be tested includes N areas to be tested, N is a positive integer greater than 1, and the light source emits N first rays at N first times, respectively, and the N first ray systems respectively correspond to the The N areas to be tested and the wavelengths of the N first rays are in the infrared wavelength range. The spatial light modulator is configured to generate N second light rays according to the N first light rays, respectively, and the wavelengths of the N second light rays are in the infrared wavelength range. The lens is configured to respectively map the N second rays to the N to-be-measured regions of the object to be tested at the N second time, and respectively reflect the N regions from the N regions to be tested The second light forms N light rays that are directed toward the projector, and the wavelengths of the N third light rays L3 are in the infrared wavelength range. The infrared receiver is configured to receive the N third rays at N third times respectively. The computing unit is coupled to the light source and the infrared receiver, respectively, for obtaining the N regions and projections of the object to be tested according to the N first time, the N second time, the N third time, and the light speed respectively N distances between the machines. Wherein, when the projector turns off the ranging function, the light source can emit visible light for projection and the infrared receiver can receive the infrared remote control signal from the infrared remote controller.

Compared with the prior art, the projector of the present invention can perform the ranging function without separately setting other components to respectively measure the distance between the projector and different regions on the projection surface, thereby estimating the geometric features of the projection surface and The surface undulation changes and the projection parameters of the projector are automatically adjusted accordingly. Therefore, even if the projection surface is not ideal (for example, the surface is uneven or irregular in shape), when the projector projects the image onto the projection surface according to the adjusted projection parameters, the image displayed on the projection surface can respond to the geometric features and surfaces of the projection surface. Fluctuating changes and trying to maintain the integrity of the picture, so it can effectively avoid the distortion or deformation of the picture displayed on the projection surface in the prior art. Elephant.

The advantages and spirit of the present invention will be further understood from the following detailed description of the invention.

1‧‧‧Projector

10‧‧‧Light source

12‧‧‧ lens

14‧‧‧Infrared receiver

16‧‧‧ arithmetic unit

17‧‧‧Digital image processing chip

18‧‧‧Shell

SLM‧‧‧Space Light Modulator

OB, OB1‧‧‧ test object

L1~L6‧‧‧first light~sixth light

D1‧‧‧First distance

D2‧‧‧Second distance

RM‧‧‧Infrared remote control

SRM‧‧‧Infrared remote control signal

R1~R25‧‧‧Down area

LN‧‧‧N light

1 is a schematic view of a projector in accordance with a preferred embodiment of the present invention.

2 is a schematic view showing the distance measurement of the object to be tested by the projector of the present invention.

FIG. 3 illustrates an embodiment in which a test object includes a plurality of regions to be tested.

4A to 4C are diagrams respectively showing the corresponding areas to be tested in which the projector emits light to the object to be tested at different times.

FIG. 5 illustrates another embodiment in which a sample to be tested includes a plurality of regions to be tested.

A projector in accordance with an embodiment of the present invention is a projector. In this embodiment, the projector of the present invention can start the ranging function without separately setting other components to respectively measure the distance between the projector and the different regions of the projection surface (ie, the object to be tested), and then estimate The geometrical features of the projection surface and the surface fluctuations are adjusted accordingly, and the projection parameters of the projector are adjusted accordingly, so that the projection screen displayed by the projection surface when the projector of the present invention projects the image onto the projection surface according to the adjusted projection parameters That is, according to the geometrical features of the projection surface and the surface fluctuations, the corresponding adjustment can be effectively maintained, so that the integrity of the projected image can be effectively maintained without being distorted as in the prior art. The phenomenon of deformation.

1 and FIG. 2, FIG. 1 is a schematic diagram of a projector according to a preferred embodiment of the present invention; and FIG. 2 is a schematic diagram showing the distance measurement of the object to be tested by the projector of the present invention.

As shown in FIG. 1, the lens 12 and the infrared receiver 14 of the projector 1 are both disposed on the housing 18, and the lens 12 and the infrared receiver 14 are disposed adjacent to each other on the housing 18. When the projector 1 has not started its ranging function and operates on the projection function, the lens 12 is used to emit projection light onto the projection surface, and the infrared receiver 14 is used to receive the infrared remote control signal SRM from the infrared remote controller RM. . That is to say, the lens 12 and the infrared receiver 14 are actually necessary components that the projector 1 is originally provided.

As shown in FIG. 2, the projector 1 may include a light source 10, a spatial light modulator SLM, a lens 12, an infrared receiver 14, an arithmetic unit 16, a digital image processing wafer 17, and a casing 18. The light source 10, the spatial light modulator SLM, the arithmetic unit 16 and the digital image processing wafer 17 are all disposed in the casing 18; the lens 12 and the infrared receiver 14 are disposed adjacent to each other on the casing 18; The unit 16 is coupled to the light source 10 and the infrared receiver 14, respectively.

When the projector 1 has not started its ranging function and operates on the projection function, the light source 10 is used to emit visible light for projection, and the spatial light modulator SLM is used to convert the light emitted by the light source 10 into Project light. That is to say, the light source 10 and the spatial light modulator SLM are actually necessary components that the projector 1 is originally provided. In practical applications, the spatial light modulator SLM and the arithmetic unit 16 can be simultaneously set in The digital image processing wafers 17 are independently disposed on the respective sides, and other necessary components (for example, a memory, an image processing unit, and the like) may be additionally disposed on the digital image processing wafer 17, without particular limitation.

When the projector 1 starts the ranging function to measure the object to be measured OB, the light source 10 emits the first light L1 at the first time, and the wavelength of the first light L1 is in the infrared wavelength range. For example, the wavelength of the first light L1 may be between 760 nanometers (nm) and 1 millimeter (mm), and preferably 940 nanometers (nm) or 850 to 860 nanometers (nm), but not This is limited to this.

When the first light L1 emitted by the light source 10 is incident on the spatial light modulator SLM, the spatial light modulator SLM generates the second light L2 according to the first light L1, and the wavelength of the second light L2 is also located at the infrared wavelength. Within the scope. For example, the wavelength of the second light L2 may be between 760 nanometers (nm) and 1 millimeter (mm), and preferably 940 nanometers (nm) or 850 to 860 nanometers (nm), but not This is limited to this.

In practical applications, the spatial light modulator SLM disposed in the projector 1 may be a Digital Micro-mirror Device (DMD), a liquid crystal projection device, or any projection device using other projection mechanisms, but not This is limited to this. For example, if the spatial light modulator SLM is a liquid crystal projection device, the first light (infrared) L1 emitted by the light source 10 enters the liquid crystal projection device and then enters the lens 12, and the present invention can also be applied. In addition, an optical component, such as a lens group or the like, may be disposed between the light source 10 and the spatial light modulator SLM, such that the first light L1 emitted by the light source 10 can first pass through the optical component and then be incident on the spatial light modulator. SLM, but not limited to this.

When the second light L2 of the spatial light modulator SLM is transmitted to the lens 12, the lens 12 will emit the second light L2 toward the object to be tested OB at the second time. It should be noted that, assuming that the time difference between the first time when the light source 10 emits the first light L1 and the second time when the lens 12 emits the second light L2 to the object OB is the first time length, the first time length It may be a known fixed length of time, or the computing unit 16 may obtain the first time length after subtracting the first time and the second time by the timer (not shown) and subtracting the second time.

When the second light L2 emitted by the lens 12 is transmitted to the object to be tested OB, the object to be tested OB reflects the second light L2 to form a third light L3 directed to the projector 1, and the wavelength of the third light L3 is also located. In the infrared wavelength range. For example, the wavelength of the third light ray L3 may be between 760 nanometers (nm) and 1 millimeter (mm), and preferably 940 nanometers (nm) or 850 to 860 nanometers (nm), but not This is limited to this.

When the third light L3 reflected by the object to be tested OB is transmitted to the projector 1, the infrared receiver 14 receives the third light L3 at the third time, and then the operation unit 16 according to the first time and the second time. The third time and the speed of light obtain a first distance D1 between the object to be tested OB and the projector 1.

It should be noted that, assuming that the time difference between the second time when the lens 12 emits the second light L2 and the third time when the infrared receiver 14 receives the third light L3 is the second time length, the operation unit 16 can first pass the timing. The device (not shown) respectively measures the first time when the light source 10 emits the first light L1 and the third time when the infrared receiver 14 receives the third light L3, and subtracts the first time from the third time to obtain the total time. length. If the first length of time is known, the arithmetic unit 16 subtracts the total length of time Knowing the first length of time, the second length of time between the second time and the third time can be smoothly determined. Finally, the operation unit 16 can obtain the first distance D1 between the object to be tested OB and the projector 1 according to the second time length and the speed of light.

In practical applications, the projector 1 can switch between the projection mode and the ranging mode as needed, and this switching can be automatically performed by the system or manually set by the user. In addition, the first light L1 emitted by the light source 10 and the third light L3 reflected by the object to be tested OB may also correspond to different infrared wavelength ranges respectively corresponding to the infrared remote control signals emitted by the remote controller, so that the object to be tested OB is The reflected third light L3 can be distinguished from the infrared remote control signal emitted by the remote controller without causing misjudgment.

For example, it is assumed that the first light L1 emitted by the light source 10 and the third light L3 reflected by the object to be tested OB correspond to the first infrared wavelength range, and the infrared remote control signal emitted by the remote controller corresponds to the second infrared wavelength range. Wherein the first infrared wavelength range is different from the second infrared wavelength range. When the projector 1 is operated in the ranging mode, the infrared ray receiver 14 is set to receive only the third light ray L3 corresponding to the first infrared wavelength range, so that when the projector 1 is to be measured by the object OB, it can be effectively avoided. The third light L3 reflected by the object to be tested OB is interfered by the infrared remote control signal emitted by the remote controller.

The above embodiment describes how the projector 1 measures the first distance D1 between the object to be tested OB and the projector 1 when the object to be tested OB contains only a single area to be tested. In another embodiment, the object to be tested OB may also include a plurality of regions to be tested. For example, the object to be tested OB shown in FIG. 3 includes a total of 25 regions R1 to R25 to be tested, but not Limited.

Referring to FIG. 2 and FIG. 4A simultaneously, it is assumed that the second light L2 emitted by the lens 12 of the projector 1 in FIG. 2 is corresponding to the first to-be-tested area R1 of the 25 to-be-tested areas R1 R R25. To the first region to be tested R1, the second light ray L2 is reflected by the first region to be tested R1 to form a third light ray L3, and the first distance D1 between the object to be tested OB and the projector 1 is actually The distance between the first region to be tested R1 on the object OB and the projector 1.

Referring to FIG. 2 and FIG. 4B simultaneously, when the projector 1 starts the ranging function, since the object to be tested OB includes a total of 25 areas R1 to R25 to be tested, when the projector 1 measures the first area to be tested R1. After the first distance D1 between the projector 1 and the projector 1, the distance between the other regions to be tested (ie, the second to-be-measured region R2 to the twenty-fifth region to be tested) and the projector 1 must be measured. Sufficient data is obtained to determine the surface undulation and geometrical characteristics of the object OB.

At the fourth time, the light source 10 emits a fourth light L4 and the fifth light L5 is generated by the spatial light modulator SLM according to the fourth light L4 and transmitted to the lens 12, and then the lens 12 is turned on at the fifth time T5. Five rays L5 are incident on the object to be tested OB. Assuming that the fifth light L5 emitted by the lens 12 of the projector 1 in FIG. 2 corresponds to the second test area R2 of the 25 test areas R1 R R25 of the object OB to be tested, the lens 12 will be the first The five ray L5 is incident on the second region R2 to be tested, and the fifth ray L5 is reflected by the second region to be tested R2 to form a sixth ray L6 directed toward the projector 1. At the sixth time T6, the infrared ray receiver 14 receives the sixth light ray L6, and the arithmetic unit 16 obtains the second region to be tested R2 and the projection according to the fourth time T4, the fifth time T5, the sixth time T6, and the speed of light. The second distance D2 between the machines 1.

In fact, the wavelengths of the fourth light L4, the fifth light L5, and the sixth light L6 are all in the infrared wavelength range. For example, the wavelengths of the fourth light L4, the fifth light L5, and the sixth light L6 may be between 760 nanometers (nm) and 1 millimeter (mm), and preferably 940 nanometers (nm) or 850~ 860 nm (nm), but not limited to this.

When the projector 1 starts the ranging function, the first distance D1 between the first to-be-measured region R1 of the object to be tested OB and the projector 1 and the second region to be tested R2 and the projector 1 are sequentially measured. After the second distance D2, the projector 1 sequentially performs the measurement of the third distance to the twenty-fifth distance between the other regions R3 to R25 of the object to be tested OB and the projector 1. For example, as shown in FIG. 4C, assuming that the light LN emitted by the lens 12 of the projector 1 corresponds to the twenty-fifth to-be-measured region R25 of the object to be tested OB, the lens 12 shoots the light LN to the second. Fifteen areas to be tested R25. The rest can be deduced by analogy, and will not be described here.

When the computing unit 16 smoothly measures the first distance D1 to the twenty-fifth distance between the projector 1 and the first to-be-measured area R1 to the twenty-fiveth to-be-measured area R25 of the 25 to-be-tested areas R1 R R25 At D25, the arithmetic unit 16 can obtain surface fluctuations and geometric features (such as geometric shapes, notches, etc.) of the object to be tested OB according to the first distance D1 to the twenty-fifth distance D25 and adjust the projection parameters of the projector 1 accordingly. .

For example, if the first distance D1 corresponding to the first to-be-tested area R1 is shorter, the first area to be tested R1 representing the object to be tested OB may be relatively convex and relatively close to the projector 1; The sixth distance D6 of the measurement area R6 is longer, and the sixth measurement area R6 representing the object to be tested OB may be relatively concave and relatively far away from the projection. If the infrared receiver 1 does not receive the reflected light of a certain area to be tested of the object to be tested OB, the operation unit 16 may determine that the object to be tested OB may have a gap in the area to be tested. The rest can be deduced by analogy, and will not be described here.

Then, when the projector 1 is to project an image to the object to be tested OB, the projector 1 can project the image to the object to be tested OB according to the adjusted projection parameter, so that the image displayed by the object to be tested OB can be displayed. The integrity of the projected image is maintained as much as possible in response to surface fluctuations and geometrical features of the object OB to avoid distortion or distortion of the projected image.

In practical applications, the geometry of the object to be tested OB is not limited to the squares shown in FIG. 3 and FIG. 4A to FIG. 4C, and may be a rectangle as shown in FIG. 5, or other rules or irregularities. Geometry can be applied without specific limitations. In addition, the measurement sequence of the distance measurement of the plurality of to-be-measured regions of the object to be tested OB, and the number and geometry of the plurality of to-be-measured regions included in the object to be tested OB are not limited to the above embodiments. There are no specific restrictions.

Compared with the prior art, the projector of the present invention can perform the ranging function without separately setting other components to respectively measure the distance between the projector and different regions on the projection surface, thereby estimating the geometric features and surfaces of the projection surface. The fluctuations are changed, and the projection parameters of the projector are automatically adjusted accordingly, so that when the projector projects the image onto the projection surface according to the adjusted projection parameters, the image displayed on the projection surface can respond to the geometric features and surface fluctuations of the projection surface. Changes and try to maintain the integrity of the picture, so it can effectively avoid the distortion or deformation of the picture displayed on the projection surface in the prior art.

The features and spirits of the present invention are intended to be more apparent from the detailed description of the preferred embodiments. On the contrary, the intention is to cover various modifications and equivalents within the scope of the invention as claimed. The features and spirit of the present invention will be more apparent from the detailed description of the preferred embodiments. On the contrary, the intention is to cover various modifications and equivalents within the scope of the invention as claimed.

Claims (15)

A projector includes: a light source, when the projector starts the ranging function to measure a sample to be tested, the light source emits a first light at a first time, and the wavelength of the first light is in the infrared a spatial light modulator for generating a second light according to the first light, wherein the wavelength of the second light is in the infrared wavelength range; a lens for using the second time The second light is directed toward the object to be tested, the object to be tested reflects the second light to form a third light incident on the projector, and the wavelength of the third light is in the infrared wavelength range; an infrared receiver The third light is received at a third time; and an arithmetic unit is coupled to the light source and the infrared receiver respectively for obtaining the first time, the second time, the third time, and the speed of light a first distance between the object to be tested and the projector; wherein, when the projector turns off the ranging function, the light source emits a visible light line for projection and the infrared receiver can receive from an infrared One remote control infrared remote control signal. The projector of claim 1, wherein the projector further comprises a housing, the light source, the spatial light modulator and the computing unit are disposed in the housing and the lens and the infrared receiver They are respectively disposed on the casing. The projector of claim 2, wherein the lens is disposed adjacent to the infrared receiver on the same side of the housing. The projector of claim 1, wherein the computing unit first subtracts the total time length between the first time and the third time by the first time and the second time After a length of time to obtain a second length of time between the second time and the third time, multiplying the second length of time by the speed of light to obtain The first distance between the object to be tested and the projector. The projector of claim 1, wherein the object to be tested comprises N regions to be tested, and N is a positive integer greater than 1, and the first light emitted by the light source is modulated by the spatial light modulator. For the second light, the second light is projected light and is projected by the lens to one of the N to-be-measured areas and the second light is reflected by the first to-be-measured area to form the second light Three rays, and the first distance is a distance between the first area to be tested and the projector. The projector of claim 5, wherein when the projector starts the ranging function, the light source emits a fourth light at a fourth time and the light source is emitted by the spatial light modulator. The fourth light is modulated into a fifth light, the wavelengths of the fourth light and the fifth light are in the infrared wavelength range, and the fifth light system corresponds to one of the N measured regions. Measuring the area, the fifth light is a projected light, and the lens projects the fifth light to the Kth to be tested area at a fifth time and reflects the fifth light from the Kth to be tested area to form a projection a sixth light of the machine, when the infrared receiver receives the sixth light at a sixth time, the operation unit obtains the Kth wait according to the fourth time, the fifth time, the sixth time, and the speed of light A Kth distance between the measurement area and the projector, K being a positive integer greater than 1 and less than or equal to N. The projector of claim 5, wherein the computing unit obtains the first between the projector and the first to-be-measured area of the N to-be-tested areas a distance to the Nth distance, the operation unit obtains a surface fluctuation of the object to be tested according to the first distance to the Nth distance, and adjusts a projection parameter of the projector according to the adjustment, so that the projector is adjusted according to the When the projection parameter projects a picture on the object to be tested, the picture can be undulated or not deformed due to the surface undulation of the object to be tested. The projector of claim 1, wherein the infrared remote control signal is The first light emitted by the light source and the third light reflected by the object to be tested respectively correspond to different infrared wavelength ranges. A projector comprising: a light source, when the projector starts the ranging function to measure a sample to be tested, if the object to be tested includes N areas to be tested, N is a positive integer greater than 1, respectively N first light rays are emitted at the first time, the N first light rays respectively corresponding to the N test regions and the wavelengths of the N first light rays are in the infrared wavelength range; a spatial light modulation And respectively, the N first rays are converted into N second rays, the N second rays are projection rays and the wavelengths of the N second rays are in the infrared wavelength range; Projecting the N second rays to the N regions to be tested correspondingly at the N second times, and respectively reflecting the N regions from the N regions to be tested The second light forms N third rays directed to the projector, and the wavelengths of the N third rays are in the infrared wavelength range; an infrared receiver is configured to receive the N at the N third times respectively a third light; and an arithmetic unit coupled to the light source and the infrared receiving And obtaining N distances between the N test areas of the object to be tested and the projector according to the N first time, the N second time, the N third time, and the light speed respectively; Wherein, when the projector turns off the ranging function, the light source emits a visible light line for projection and the infrared receiver can receive an infrared remote control signal from an infrared remote controller. The projector of claim 9, wherein the projector further comprises a housing, the light source, the spatial light modulator and the computing unit are disposed in the housing And the lens and the infrared receiver are respectively disposed on the housing. The projector of claim 10, wherein the lens is disposed adjacent to the infrared receiver on the same side of the housing. The projector of claim 9, wherein the computing unit first subtracts a total length of time between the first time and the third time by a first time between the first time and the second time After a length of time to obtain a second length of time between the second time and the third time, multiplying the second length of time by the speed of light to obtain the first distance between the object to be tested and the projector . The projector of claim 9, wherein when the computing unit respectively obtains the N distances between the N areas to be tested of the object to be tested and the projector, the operation unit is based on the N The distance of the surface of the object to be tested is varied and the projection parameter of the projector is adjusted, so that the projector can project a picture on the object according to the adjusted projection parameter, and the image can be The surface of the object is undulating without being distorted or deformed. The projector of claim 9, wherein when the computing unit respectively obtains the N distances between the N areas to be tested of the object to be tested and the projector, the operation unit is based on the N The distance determines a geometric feature of the object to be tested. The projector of claim 9, wherein the infrared remote control signal and the N first light rays emitted by the light source and the N third light rays reflected by the object to be tested respectively correspond to different infrared rays. The wavelength range.