CN100498502C - Projector - Google Patents
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- CN100498502C CN100498502C CNB2004100741804A CN200410074180A CN100498502C CN 100498502 C CN100498502 C CN 100498502C CN B2004100741804 A CNB2004100741804 A CN B2004100741804A CN 200410074180 A CN200410074180 A CN 200410074180A CN 100498502 C CN100498502 C CN 100498502C
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Abstract
This invention provides a projector, which contains ultrasonic wave convertor for generating wide frequency band acoustic signal, ultrasonic wave loudspeaker, and projector main unit having projection optical system. Said invention can obtain stereo surround system or 5.1 channel surround system.
Description
Technical field
The present invention relates to load the projector of the ultrasonic speaker that constitutes by the ultrasonic transducer that in broadband, can produce certain high sound pressure.
Background technology
In the past, because projector uses when mainly doing demonstration in meeting etc., so loudspeaker needn't be set especially on projector main body.This be because, the speaker describes the projector projection data on screen in person, this illustrates and blazes abroad by the loudspeaker of microphone from the meeting-place as acoustic information.
But, because popularizing and trend that giant-screen leads of DVD etc. from now on is envisioned that the occasion of utilization in family expenses market, education and recreation market etc. can increase.When using projector as the giant-screen mapping device, each family and classroom need be equipped with sound system.But, in these application scenarios, generally do not possess the time that is used for that the space of stereo surround system or 5.1ch surrounding system is set and carries out equipment layout, and cost is also very high.Therefore, projector is not almost having value aspect the instrument of home theater and study teaching material etc.
Therefore, consider the loudspeaker that uses in the radio cassette player is installed in the main body of projector, still, if common loudspeaker is installed in the projector, then because the volume deficiency can not provide enough sound equipments.In addition, even in the main body of projector loudspeaker is set, and therefrom sound, also can produce following problem: the reflection that mirrors is the position at screen, and its position with the generation source of sound is different, therefore, in any case all make the people feel inharmonious.
In addition, also proposed to utilize the ultrasonic speaker of ultrasonic transducer to be installed in the interior scheme (for example, with reference to patent documentation 1) of projector, Fig. 8 represents the structure of ultrasonic speaker in the past.Ultrasonic speaker has: produce the audible frequency ripple oscillation source 81 of audio-band signal, carrier oscillation source 82, modulator 83, power amplifier 84 and the ultrasonic transducer 85 of generation carrier wave.
In said structure, utilization is from the signal of audible frequency ripple oscillation source 81 outputs, by modulator 83, the carrier wave of the ultrasound wave frequency band of 82 outputs from the carrier oscillation source is modulated, and used the modulation signal that amplifies by power amplifier 84 that ultrasonic transducer 85 is driven.Its result utilizes ultrasonic transducer 85 that above-mentioned modulation signal is converted to the sound wave of finite amplitude level, and this sound wave is launched into (in the air) in the media, and reproduces the signal tone of original audio-band according to the nonlinear effect of media (air).
In this case, the reproduction range of the reproducing signal of audio-band is towards the scope of emitting axial wave beam shape from ultrasonic transducer 85.
Herein, the structure of the ultrasonic transducer of ultrasonic speaker use in the past as shown in Figure 9.Ultrasonic transducer in the past typically uses the mode of resonance of piezoelectric ceramics as vibrating elements.Ultrasonic transducer shown in Figure 9 is as vibrating elements, uses piezoelectric ceramics, carries out the bi-directional conversion (hyperacoustic transmission and reception) of electric signal to ultrasound wave, ultrasound wave to electric signal.Bimorph type ultrasonic transducer shown in Fig. 9 (A) is made of 2 piezoelectric ceramics 91,92, taper device 93, shell 94, lead-in wire 95,96 and sound film 97. Piezoelectric ceramics 91,92 is fitted mutually, is connected with lead-in wire 95 and lead-in wire 96 on its binding face and opposing face respectively.
On the other hand, the single piezoelectric chip type ultrasonic transducer shown in Fig. 9 (B) is made of 1 piezoelectric ceramics 101, shell 102, lead-in wire 103,104, internal wiring 105 and glass sheet 106.Piezoelectric ceramics 101 is connected with lead-in wire 103 by internal wiring 105, simultaneously, and shell 102 ground connection.
There is following shortcoming in the mode of resonance ultrasonic transducer: owing to be the resonance phenomena of utilizing piezoelectric ceramics, so the characteristic of hyperacoustic transmission and reception is only good in the narrow frequency band of its resonance frequency periphery, so tonequality is relatively poor.
Patent documentation 1: the spy opens flat 11-262084 communique
Summary of the invention
The present invention proposes in view of above situation, it is a kind of by using the ultrasonic speaker that is made of the ultrasonic transducer that can produce certain high sound pressure in broadband that its purpose is to provide, do not need essential in the past huge sound system just can realize the acoustics of using stereo surround system or 5.1ch surrounding system etc. to be obtained, and the projector of being convenient to move.
In order to achieve the above object, the present invention's 1 projector is characterised in that ultrasonic speaker and projector main body constitute one, this ultrasonic speaker, be used to export the reproducing signal as the audio-band signal tone, it has: signal source, the signal wave of generation audio-band; The carrier wave feed unit generates the also carrier wave of output ultrasonic wave frequency band; Reproduction range control and treatment portion, it is controlled the audible sound reproduction range by the frequency of the above-mentioned carrier wave of control; Modulating unit is modulated above-mentioned carrier wave with above-mentioned signal wave; And electrostatic ultrasonic transducer, under the driving of the modulation signal of exporting from this modulating unit, the broadband acoustic signal that the output of can vibrating by this modulation signal is converted to the sound wave of finite amplitude level is launched in media, this projector main body has: the reflection generation unit generates reflection; And projection optical system, the reflection that this reflection generation unit is generated projects on the projecting plane.
In addition, the present invention's 2 projector is characterised in that, in the present invention's 1 projector, the sound wave emissions face of above-mentioned ultrasonic transducer is a flat shape.
In addition, the present invention's 3 projector is characterised in that, in the present invention's 1 projector, constitute be arranged on the optical system on the above-mentioned projector main body and reflection projected to the optical axis of the projector lens on the projecting plane consistent with the normal direction of the sound wave emissions face of ultrasonic transducer.
In addition, the present invention's 4 projector is characterised in that, in the present invention's 1 projector, above-mentioned ultrasonic transducer is fixedly installed on the above-mentioned projector main body, and on the position of the barrier of a part that is located at above-mentioned projector main body in its front or projector main body can not become sound wave emissions the time.
In addition, the present invention's 5 projector is characterised in that, in the present invention's 1 projector, adopt following structure: above-mentioned ultrasonic transducer is received to when not using projector in the above-mentioned projector main body, appears at outside the above-mentioned projector main body when using projector.
In addition, the present invention's 6 projector is characterised in that, in the present invention's 1 projector, adopt following structure: the ultrasonic speaker that is made of above-mentioned ultrasonic transducer etc. is single, has the function as the monophony sound source.
In addition, the present invention's 7 projector is characterised in that, in the present invention's 1 projector, a plurality of ultrasonic speakers that are made of above-mentioned ultrasonic transducer etc. are set, and the normal direction of sound wave emissions face that constitutes at least one ultrasonic transducer in a plurality of ultrasonic transducers of a plurality of ultrasonic speakers respectively is consistent with the optical axis of above-mentioned projector lens.
Projector has by changing the advantage that giant display that position relation with screen just can change such other of image size does not possess, and has been best suited for considering the family expenses mapping device of the configuration pattern of all size, shape, furniture.And, if use the one-piece type ultrasonic speaker of projector main body of the present invention, can be transported in any one room as cassette radio recorder, project to and just can enjoy large-scale picture harmony sound on specific screen or the wall simultaneously.In addition, in the current school that does not have complete audible environment etc., its value also increases day by day.
In addition, the invention provides a kind of projector, in this projector, use can vibrate the converter of broadband acoustic signal (sound wave of ultrasound wave frequency band) as the ultrasonic transducer that constitutes ultrasonic speaker, control reproduction range on the space of reproducing signal of audio-band by changing carrier frequency, thus, do not need essential in the past huge sound system just can realize the acoustics of using stereo surround system or 5.1ch surrounding system etc. to be obtained, and carrying easily.
Description of drawings
Fig. 1 is the block scheme of circuit structure of the projector of expression embodiment of the present invention.
Fig. 2 is the figure of the concrete structure of the ultrasonic transducer in the presentation graphs 1.
Fig. 3 is the performance plot of the frequency characteristic of expression ultrasonic transducer shown in Figure 2.
Fig. 4 is the synoptic diagram of the state the when ultrasonic transducer that loaded carries out the reproduction of reproducing signal in the projector of expression embodiment of the present invention.
Fig. 5 is the appearance assumption diagram that is illustrated in when in the projector of embodiment of the present invention 1 ultrasonic transducer only being set.
Fig. 6 is the appearance assumption diagram that is illustrated in when in the projector of embodiment of the present invention 2 ultrasonic transducers being set.
Fig. 7 is the appearance assumption diagram when being illustrated in the ultrasonic transducer that is provided with in the projector of embodiment of the present invention more than 3.
Fig. 8 is a block scheme of representing the circuit structure of ultrasonic speaker in the past.
Fig. 9 is the figure of the structure example of expression mode of resonance ultrasonic transducer.
Among the figure: 1: projector; 2: the projecting plane; 10: operation inputting part; 12: the reproduction range configuration part; 13: reproduction range control and treatment portion; 14: sound/image signal recapiulation; 16: the carrier oscillation source; 18: modulator; 20: projector main body; 24: ultrasonic transducer; 200: the reflection generating unit; 202: projection optical system; 2020: projector lens.
Embodiment
Below, with reference to accompanying drawing embodiments of the present invention are described in detail.The electrical structure of the projector of embodiments of the present invention as shown in Figure 1.The projector 1 of embodiments of the present invention has: operation inputting part 10, reproduction range configuration part 12, sound/image signal recapiulation 14, carrier oscillation source 16, modulator 18, power amplifier 22, the ultrasonic speaker and the projector main body 20 that are made of ultrasonic transducer 24.
Projector main body 20 has: the reflection generating unit 200 of generation reflection and the reflection that will generate project to the projection optical system 202 on the projecting plane.
The projector 1 of present embodiment has adopted and has made ultrasonic speaker and projector main body 20 incorporate structures.
The user is by keyboard operation operation inputting part 12, can will specify the data of the reproduction range of reproducing signal (signal tone) to input to reproduction range configuration part 12, after having imported these data, stipulated that the frequency of carrier wave of the reproduction range of reproducing signal promptly is set and is held.The setting of the reproduction range of reproducing signal is by specifying reproducing signal to carry out towards the axial arrival distance of emission from the sound wave emissions of ultrasonic transducer 22.
In addition, reproduction range configuration part 12 can utilize from the control signal of sound/image signal recapiulation 14 outputs and set the frequency of carrier wave according to image content.
In addition, reproduction range control and treatment portion 13 has following function: with reference to the setting content of reproduction range configuration part 12, carrier oscillation source 16 is controlled, become the frequency of the carrier wave reproduction range that is set, that generated by carrier oscillation source 16 with change.For example, as the internal information of reproduction range configuration part 12, set corresponding carrier frequency be 50kHz above-mentioned apart from the time, the vibration that frequency is 50kHz is carried out in control carrier oscillation source 16.
Reproduction range control and treatment portion 13 has storage part, its prior storage representation reproducing signal from the sound wave emissions face of the ultrasonic transducer 22 of regulation reproduction range along the emission shaft direction the distance of process and the table of the relation between the carrier frequency.Relation between the frequency by calculating carrier signal and the arrival distance of above-mentioned reproducing signal can obtain the data of this table.
Reproduction range control and treatment portion 13 setting contents according to reproduction range configuration part 12, with reference to above-mentioned table, the frequency of the corresponding carrier wave of range information of obtaining and setting, and control carrier oscillation source 16 makes it with this hunting of frequency.
Sound/image signal recapiulation 14 is to use the DVD player of DVD for example as the reflection medium, and the voice signal that reproduces is exported to modulator 18, image signal is exported to the reflection generating unit 200 of projector main body 20.
In addition, in the present embodiment, be to use DVD player as sound/image signal recapiulation 14, but be not limited to this, also can use the transcriber of reproduction from the vision signal of outside input.
In addition, sound/image signal recapiulation 14 has the function of output to the control signal of reproduction range configuration part 12 indication reproduction ranges, so that in order to produce the acoustics of the reflection occasion that is fit to reproduction, dynamically change the reproduction range that reproduces sound.
Ultrasonic transducer 24 has following function: under the driving of modulator 18 by the modulation signal of power amplifier 22 outputs, this modulation signal is converted to the sound wave of finite amplitude level and is transmitted in the media signal tone (reproducing signal) of reproduction audio-band.
This ultrasonic transducer 24 for example is the electrostatic converter that can generate broadband acoustic signal (ultrasound wave).Ultrasonic transducer 24 can not be an electrostatic so long as can generate the converter of wide band acoustic signal.
Projection optical system 202 has following function: will be presented on the projecting plane that reflection on the display projects to screen of being arranged at projector main body 20 the place aheads etc.
The concrete structure of ultrasonic transducer 24 as shown in Figure 2.Electrostatic ultrasonic transducer shown in Figure 2 uses the dielectric 31 (insulator) of the thick PET (pet resin) of 3～10 μ m etc. as vibrating mass.Dielectric 31 and the top electrode 32 that is formed by metal formings such as aluminium carry out processing such as evaporation by face on this dielectric 31, form as one, and simultaneously, the bottom electrode 33 that is formed by brass is configured to contact with the lower face of dielectric 31.This bottom electrode 33 52 links to each other with lead-in wire, simultaneously, is fixed on the substrate 35 that is made of phenoplast etc.
In addition, top electrode 32 53 links to each other with lead-in wire, and this goes between and 53 links to each other with direct current biasing power supply 50.Usually utilize this direct current biasing power supply 50 to adsorb the dc offset voltage of usefulness, make top electrode 32 be adsorbed on bottom electrode 33 sides to the top electrode that top electrode 32 applies 50～150V.The 51st, ac signal which is equivalent to the output (AC50～150Vp-p) of the power amplifier 22 among Fig. 1.
Dielectric 31, top electrode 32 and substrate 35 are fixed by becket 36,37,38, net 39 and shell 30.
Be formed with a plurality of small grooves on the face of dielectric 31 sides of bottom electrode 33 with the tens of～hundreds of μ m that are inhomogeneous shape.This small groove is owing to the space that becomes between bottom electrode 33 and the dielectric 31, so the changes in distribution of the electrostatic capacitance between top electrode 32 and the bottom electrode 33 is little.This small groove at random is to use the surface of file rasion bottom electrode 33 to form by manual operations.In electrostatic ultrasonic transducer, by the interstitial like this size numerous capacitor different with the degree of depth, the frequency characteristic of ultrasonic transducer will become the broadband shown in the curve Q1 among Fig. 3.
In the ultrasonic transducer 24 of said structure, applying to top electrode 32 under the state of dc offset voltage, can between top electrode 31 and bottom electrode 33, apply modulation signal (output of power amplifier 22).By the way, shown in the curve Q2 among Fig. 3, the centre frequency of the frequency characteristic of the ultrasonic transducer of mode of resonance (resonance frequency of piezoelectric ceramics) for example is 40kHz, with respect to the centre frequency that becomes maximum sound pressure ± frequency of 5kHz on, with respect to maximum sound pressure be-30dB.And the frequency characteristic of the ultrasonic transducer of the broadband oscillation mode of said structure is smooth near from 40kHz to 100kHz, when 100kHz, compares with maximum sound pressure, for about ± 6dB.
Then, the action by the projector 1 of the embodiments of the present invention of said structure is described.At first,, specify the setting of the data (range information) of the reproduction range of reproducing signal from 10 pairs of reproduction range configuration parts 12 of operation inputting part, in sound/image signal recapiulation 14, form and reproduce indication by user's keyboard operation.Its result, in reproduction range configuration part 12, set the range information of having stipulated reproduction range, reproduction range control and treatment portion 13 obtains the range information of setting in reproduction range configuration part 12, and with reference to the table in the storage part of establishing in being stored in, obtain frequency with the corresponding carrier wave of range information of above-mentioned setting, and control carrier oscillation source 16, to generate the carrier wave of this frequency.
Its result, carrier oscillation source 16 generates the carrier wave of the corresponding frequency of range information that sets with reproduction range configuration part 12, and exports to modulator 18.
On the one hand, sound/image signal recapiulation 14 is exported to modulator 18 with voice signal, simultaneously, image signal is exported to the reflection generating unit 200 of projector main body 20.
In reflection generating unit 200, according to the image signal of being imported, come driving display, generate reflection, and show.Be presented at the reflection on this display, utilize projection optical system 202 to project on the projecting plane, for example on the screen.
On the other hand, in modulator 18, utilize from the voice signal of sound/image signal recapiulation 14 outputs the carrier waves of 16 outputs from the carrier oscillation source are carried out the AM modulation, and export to power amplifier 22.
The modulation signal that is amplified by power amplifier 22 is applied between the top electrode 32 and bottom electrode 33 of ultrasonic transducer 24, and this modulation signal is transformed to the sound wave (acoustic signal) of finite amplitude level, and is launched into (in the air) in the media.
Herein, nonlinear effect to media (air) is narrated simply, when the ultrasound wave that is transmitted into (in the air) in the media by ultrasonic transducer is propagated, is accompanied by this propagation, the part velocity of sound high in acoustic pressure accelerates, and be slack-off at the part velocity of sound that acoustic pressure is low.Its result, the distortion that has produced waveform.
When the signal (carrier signal) of ultrasonic waves transmitted frequency band being modulated (AM modulation) with the signal of audio-band, result according to above-mentioned waveform distortion, as can be known: the signal wave and the carrier separation of ultrasound wave frequency band of the audio-band of using in when modulation, and obtain reducing with the form from demodulation.At this moment, the propagation of reproducing signal becomes the wave beam shape because of hyperacoustic characteristic, and is different fully with common loudspeaker, and it reproduces sound to specific direction.
In the projector of present embodiment, from the reproducing signal of the wave beam shape of ultrasonic transducer 24 outputs that constitute ultrasonic speaker by optical system 202 to the emission of the projecting plane (screen) of projection reflection, and be projected the face reflection and spread.Because the frequency of the carrier wave that corresponding reproduction range configuration part 12 sets, distance when the sound wave emissions face of ultrasonic transducer 24 is separated from carrier wave to the reproducing signal on its emission shaft direction (normal direction), and wave beam amplitude (extended corner of the wave beam) difference of carrier wave, reproduction range changes thus.
State when the reproducing signal of the ultrasonic speaker that is made of ultrasonic transducer 24 grades in the projector of present embodiment reproduces as shown in Figure 4.In projector 1, by the modulation signal that utilizes voice signal that carrier wave is modulated, when ultrasonic transducer is driven, under the low situation of the carrier frequency that sets by reproduction range configuration part 12, the distance when the sound wave emissions face of ultrasonic transducer 24 is separated from carrier wave to the reproducing signal on emission shaft direction (normal direction of sound wave emissions face), elongated to the distance of reproducing the place.
So, the wave beam of the reproducing signal of the audio-band of reproducing is not expanded fully and has just been arrived projecting plane 2, under this state, because the reflection on projecting plane 2, reproduction range becomes the range of audibility A shown in the dotted arrow among Fig. 4, becomes the state that can only hear reproducing signal (reproduction sound) in from projecting plane 2 to distant and narrow scope.
To this, the carrier frequency of being set by reproduction range configuration part 12 is under than the high situation of above-mentioned situation, concentrate from the situation that the acoustic ratio carrier frequency of the sound wave emissions surface launching of ultrasonic transducer 24 is low, but the distance when the sound wave emissions face of ultrasonic transducer 24 is separated from carrier wave to the reproducing signal on its emission shaft direction (normal direction of sound wave emissions face), shorten to the distance of reproducing the place.
So, the wave beam of the reproducing signal of the audio-band of reproducing arrives projecting plane 2 with the state that just spread before arriving projecting plane 2, under this state, because the reflection on projecting plane 2, reproduction range becomes the range of audibility B shown in the solid arrow among Fig. 4, becomes the state that can hear reproducing signal (reproduction sound) in from projecting plane 2 to closer and broad scope.
Then, with reference to Fig. 5～Fig. 7 the example that is provided with of the ultrasonic speaker in the projector of embodiments of the present invention is described.
The example that only is provided with 1 ultrasonic speaker that is made of ultrasonic transducer is by shown in Figure 5.In this case, bringing into play the function of monophony sound source.Herein, in Fig. 5 (A), (B), be set to: the sound wave emissions face of ultrasonic transducer 24 is a flat shape, and the normal direction of sound wave emissions face that constitutes the optical axis be arranged on the projection optical system 202 in the projector main body 20 and reflection be projected in the projector lens 2020 on the projecting plane and ultrasonic transducer 24 is consistent.
Being provided with in the example of Fig. 5 (a), ultrasonic transducer 24 is arranged on the right horizontal side of projector lens 2020, can certainly be arranged on left horizontal side.The situation of this method to set up because the front of projector main body 20 is the plane, so make easily projector lens 2020 optical axis direction, be that screen orientation is consistent with the normal direction of the sound wave emissions face of ultrasonic transducer 24.
As long as in addition, in Fig. 5 (b), ultrasonic transducer 24 is arranged on the upside of projector lens 2020, but on projector main body 20, its position can also can be in the left and right sides in centre.Importantly the normal direction of the sound wave emissions face of the optical axis direction of projector 2020 and ultrasonic transducer 24 is consistent.
Then, be provided with 2 ultrasonic speakers, be ultrasonic transducer 24 example as shown in Figure 6.
The situation of 2 loudspeakers can obtain the acoustics of stereophonic sound system.In Fig. 6 (a), show the example that is arranged on projector lens 2020 left and right sides, in Fig. 6 (b), show the symmetrical locational example that is arranged on above the projector main body 20.Dispose 2 ultrasonic speakers 24 and be not limited to this kind situation, also can adopt a ultrasonic transducer 24 is configured on the horizontal side direction of projector lens 2020, another ultrasonic transducer 24 is configured in structure above the projector lens 2020.
3 or 3 above ultrasonic speakers are set, be ultrasonic transducer 24 example as shown in Figure 7.
Fig. 7 (a) shows the example that is provided with 4 ultrasonic transducers 24.Be that the left and right sides disposes 2 example on projector main body 20 2 of the left and right sides of projector lens 2020 configurations, but all ultrasonic transducers 24 do not need all towards screen orientation.Any several oneself reflection sounds in many ways that also can be used in a plurality of ultrasonic transducers 24.
Fig. 7 (b) shows the example that is provided with 3 ultrasonic transducers 24.It is also routine same with being provided with of Fig. 7 (a), and ultrasonic transducer 24 that will be not all is all towards screen.Also can adopt the acoustic structure that can obtain to increase on loudspeaker subwoofer at stereo surround.That is, for example, be equivalent to the ultrasonic transducer 24 of stereo surround, realize and only the ultrasonic transducer 24 that is equivalent to subwoofer is set in the side of projector main body 20 with loudspeaker by only being provided with in the left and right sides of projector lens 2020.
Fig. 7 (c) shows and will be arranged on the example that projector main body 20 2 top ultrasonic transducers 24 are obvious horizontally set.Because it is strong to constitute the directive property of ultrasonic transducer 24 of ultrasonic speaker, so in this case,, can be heard to the signal tone of the transverse direction emission of projector main body 20 transverse direction reflected back from projector main body 20.Also can be with same idea to the rear of projector main body 20 and the top sound that transmits.In addition, under the situation that a plurality of ultrasonic transducers 24 more than 2 or 2 are set on the projector main body 20, at least 1 ultrasonic transducer 24 is configured to make the normal direction of sound wave emissions face of this ultrasonic transducer 24 consistent with the optical axis of projector lens 2020.
If use a plurality of ultrasonic transducers 24 like this, then can form the such audible environment of 5.1ch surrounding system in the past.
In addition, being provided with in the example of the ultrasonic transducer shown in Fig. 5 to 7 24, ultrasonic transducer 24 whichsoever all is set regularly, but be not limited to this, also ultrasonic transducer can be arranged to intake type, promptly when using, it is not accommodated in the projector main body 20, and only just ultrasonic transducer is taken out from projector main body 20 in use.
Claims (7)
1, a kind of projector is characterized in that, ultrasonic speaker and projector main body constitute one,
This ultrasonic speaker is used to export the reproducing signal as the audio-band signal tone, and it has: signal source, the signal wave of generation audio-band; The carrier wave feed unit generates the also carrier wave of output ultrasonic wave frequency band; Reproduction range control and treatment portion, it is controlled the audible sound reproduction range by the frequency of the above-mentioned carrier wave of control; Modulating unit is modulated above-mentioned carrier wave with above-mentioned signal wave; And the electrostatic ultrasonic transducer, under the driving of the modulation signal of exporting from this modulating unit, the broadband acoustic signal that the output of can vibrating by this modulation signal is converted to the sound wave of finite amplitude level is launched in media,
This projector main body has: the reflection generation unit generates reflection; And projection optical system, the reflection that this reflection generation unit is generated projects on the projecting plane.
2, projector according to claim 1 is characterized in that, the sound wave emissions face of above-mentioned ultrasonic transducer is plane.
3, projector according to claim 1 is characterized in that, constitute be arranged on the optical system on the above-mentioned projector main body and reflection projected to the optical axis of the projector lens on the projecting plane consistent with the normal direction of the sound wave emissions face of ultrasonic transducer.
4, projector according to claim 1, it is characterized in that, above-mentioned ultrasonic transducer is fixedly installed on the above-mentioned projector main body, and on the position of the barrier of a part that is located at above-mentioned projector main body in its front or projector main body can not become sound wave emissions the time.
5, projector according to claim 1 is characterized in that, adopts following structure: above-mentioned ultrasonic transducer is received to when not using projector in the above-mentioned projector main body, appears at outside the above-mentioned projector main body when using projector.
6, projector according to claim 1 is characterized in that, adopts following structure: the ultrasonic speaker that is made of above-mentioned ultrasonic transducer etc. is single, has the function as the monophony sound source.
7, projector according to claim 1, it is characterized in that, a plurality of ultrasonic speakers that are made of above-mentioned ultrasonic transducer etc. are set, and the normal direction of sound wave emissions face that constitutes at least one ultrasonic transducer in a plurality of ultrasonic transducers of a plurality of ultrasonic speakers respectively is consistent with the optical axis of above-mentioned projector lens.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2004100741804A CN100498502C (en) | 2004-09-01 | 2004-09-01 | Projector |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2004100741804A CN100498502C (en) | 2004-09-01 | 2004-09-01 | Projector |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1743942A CN1743942A (en) | 2006-03-08 |
| CN100498502C true CN100498502C (en) | 2009-06-10 |
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| Application Number | Title | Priority Date | Filing Date |
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| CNB2004100741804A Expired - Fee Related CN100498502C (en) | 2004-09-01 | 2004-09-01 | Projector |
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| Country | Link |
|---|---|
| CN (1) | CN100498502C (en) |
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