1. An optical sensor, comprising:

a single-channel light sensing element;

the tunable filter is arranged on the light incident side of the single-channel photosensitive element and has a plurality of light transmission modes;

and the driving piece is connected with the tunable filter and is used for driving the tunable filter to be switched in a plurality of light transmission modes so as to transmit light with different central wavelengths.

2. The optical sensor of claim 1,

the driver switches the light transmission mode by adjusting a voltage applied to the tunable filter.

3. The optical sensor of claim 2, wherein the tunable filter comprises:

a plurality of wave plates stacked in an incident direction of light, each of the plurality of wave plates including:

a liquid crystal layer;

a quartz layer located at one side of the liquid crystal layer;

the polaroid is arranged on one side, away from the liquid crystal layer, of the quartz layer;

the first glass substrate is arranged between the liquid crystal layer and the quartz layer;

and the second glass substrate is arranged on one side of the liquid crystal layer, which is deviated from the quartz layer.

4. The optical sensor of claim 3,

the driving pieces are connected with the liquid crystal layers in the wave plates in a one-to-one correspondence mode.

5. The optical sensor according to any one of claims 1 to 4,

the tunable filter is positioned right above the single-channel photosensitive element.

6. The optical sensor of any one of claims 1 to 4, wherein the single channel light sensing element comprises a photodiode or a phototransistor.

7. An electronic device, comprising:

the shell assembly is provided with a containing cavity and a light channel which are communicated; and

the optical sensor of any one of claims 1 to 6, at least a portion of the optical sensor corresponding to the light channel being disposed within the receiving cavity.

8. The electronic device of claim 7, wherein the electronic device comprises:

the processor is connected with the optical sensor and used for controlling the tunable filter of the optical sensor to sequentially operate a plurality of light transmission modes, and the single-channel photosensitive element acquires light ray data corresponding to each light transmission mode.

9. The electronic device of claim 7, wherein the electronic device comprises:

and at least part of the light guide piece is arranged in the light channel and is positioned at the light inlet side of the optical sensor.

10. The electronic device of claim 9,

the light inlet end of the light guide member extends to the entrance of the light channel.

Background

In the related art, a commonly used optical sensor is a multi-channel type, and multispectral sensing is realized by spatially arranging photodiodes with different light sensing curves. For example, the photodiode for sensing red light is an R channel, the photodiode for sensing green light is a G channel, the photodiode for sensing blue light is a B channel, the photodiode for sensing infrared light is an I channel, and the photodiode for sensing broad spectrum light is a W channel.

However, due to the trend of light and thin electronic devices, the space for accommodating the optical sensor in the electronic device is also getting smaller and smaller. On one hand, when the installation space in the electronic device is narrow, that is, the installation space only allows one photodiode to be placed, the multi-channel optical sensor is eliminated, and on the other hand, because of the compact installation space, the consistency of the field angles of the channels in the optical sensor is relatively poor, so that the accuracy of the result of multispectral detection is reduced, and for the same light source, the color temperature and the color information obtained by the optical sensor are deviated under different incident angles.

In addition, the existing optical sensor includes a single-channel optical sensor, which can only recognize a relatively large wavelength band (the wavelength band includes a plurality of colors), and cannot specifically recognize a specific color band, which limits the range of use of the optical sensor.

Disclosure of Invention

The application aims to provide an optical sensor and electronic equipment, and at least solves one of the problems that a multi-channel optical sensor in the related technology occupies a large area, the detection accuracy is low, and the single-channel optical sensor cannot perform targeted identification on specific color wave bands.

In order to solve the technical problem, the present application is implemented as follows:

in a first aspect, an embodiment of the present application provides an optical sensor, which includes:

a single-channel light sensing element;

the tunable filter is arranged on the light incident side of the single-channel photosensitive element and has a plurality of light transmission modes;

and the driving piece is connected with the tunable filter and is used for driving the tunable filter to be switched in a plurality of light transmission modes so as to transmit light with different central wavelengths.

In a second aspect, an embodiment of the present application provides an electronic device including the optical sensor as provided in the first aspect.

In an embodiment of the present application, an optical sensor includes a single-channel photosensitive element, a tunable filter, and a driving member, wherein the single-channel photosensitive element is capable of converting an optical image on a photosensitive surface into an electrical signal in a proportional relationship with the optical image by using a photoelectric conversion function. The tunable filter is arranged on the light incident side of the single-channel photosensitive element and has a plurality of light transmission modes, and the tunable filter can transmit light with specified wavelength in different light transmission modes. The driving part is connected with the tunable filter and used for controlling the tunable filter to be switched under a plurality of light transmission modes, so that the tunable filter can penetrate through light with different central wavelengths, and the single-channel photosensitive element can sense the light with different central wavelengths in a targeted manner. This application sets up the tunable filter who has multiple printing opacity mode through the income light side at single channel light sensing element, thereby can make single channel light sensing element carry out the perception to appointed light under every printing opacity mode, and need not to inject single channel light sensing element's area, can set up single channel light sensing element into the wide spectrum light sensing device of single channel, thereby ensure that single channel light sensing element's angle of view uniformity is better, the detection accuracy who avoids existence among the correlation technique is low, it is higher to the installation space demand, can't carry out pertinence discernment scheduling problem to concrete colour.

Additional aspects and advantages of the present application will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the present application.

Drawings

The above and/or additional aspects and advantages of the present application will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a schematic structural diagram of an electronic device according to an embodiment of the present application;

FIG. 2 is a schematic diagram of a portion of a liquid crystal tunable color filter of an optical sensor according to an embodiment of the present application;

fig. 3 is a partial structural schematic diagram of an electronic device according to an embodiment of the application.

Reference numerals:

110 tunable filter, 111 liquid crystal layer, 112 quartz layer, 113 polarizer, 114 first glass substrate, 115 second glass substrate,

120 a single-channel light-sensing element,

200 an electronic device to be used in a mobile communication system,

210 a processor for the processing of the received data,

220, a light channel 221, a light channel,

230 a light guide.

Detailed Description

Reference will now be made in detail to embodiments of the present application, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary only for the purpose of explaining the present application and are not to be construed as limiting the present application. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

The features of the terms first and second in the description and in the claims of the present application may explicitly or implicitly include one or more of such features. In the description of the present application, "a plurality" means two or more unless otherwise specified. In addition, "and/or" in the specification and claims means at least one of connected objects, a character "/" generally means that a preceding and succeeding related objects are in an "or" relationship.

In the description of the present application, it is to be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the present application and for simplicity in description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting of the present application.

In the description of the present application, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood in a specific case by those of ordinary skill in the art.

An optical sensor and an electronic device 200 according to an embodiment of the present application are described below with reference to fig. 1 to 3.

As shown in fig. 1 and 3, an optical sensor according to some embodiments of the present application includes a single-channel photosensitive element 120, a tunable filter 110, and a driver, where the tunable filter 110 is disposed on an incident light side of the single-channel photosensitive element 120, and the tunable filter 110 has a plurality of light transmission modes. The driver is connected to the tunable filter 110, and is used to drive the tunable filter 110 to switch between a plurality of light transmission modes to transmit light with different center wavelengths.

In this embodiment, the optical sensor includes a single-channel light-sensing element 120, a tunable filter 110, and a driver, wherein the single-channel light-sensing element 120 can convert the light image on the light-sensing surface into an electrical signal proportional to the light image by using a photoelectric conversion function. The tunable filter 110 is disposed on the light incident side of the single-channel light-sensing element 120, the tunable filter 110 has a plurality of light transmission modes, and the tunable filter 110 can transmit light with a specified wavelength in different light transmission modes. The driving member is connected to the tunable filter 110, and the driving member is configured to control the tunable filter 110 to switch in a plurality of light transmission modes, so that the tunable filter 110 transmits light with different central wavelengths, and the single-channel light sensing element 120 performs targeted sensing on the light with different central wavelengths. This application sets up tunable filter 110 that has multiple printing opacity mode through the income light side at single channel photosensitive element 120, thereby can make single channel photosensitive element 120 to appointed light under every printing opacity mode carry out the perception, and need not to prescribe a limit to single channel photosensitive element 120's area, can set up single channel photosensitive element 120 into the wide spectrum photosensitive device of single channel, that is to say, single channel photosensitive element 120 includes a photodiode, thereby it is better to ensure single channel photosensitive element 120's angle of view uniformity, it is low to avoid the detection accuracy that exists among the correlation technique, it is higher to the installation space demand, can't carry out pertinence discernment scheduling problem to specific colour. The application adopts the single-channel photosensitive element 120 and the tunable filter 110 to work in a time-sharing way, replaces an array type multi-channel sensor in the related technology, and realizes single-channel multi-spectral optical sensing.

It should be noted that the single-channel light sensing element 120 can sense light intensity over a wide spectral range and convert the light into electricity. Tunable filter 110 has multiple transmission modes, and in one transmission mode, a given center wavelength and bandwidth can be transmitted. Further, the light transmission modes of the tunable filter 110 include a first light transmission mode and a second light transmission mode, and the specified light corresponding to the first light transmission mode includes two central wavelengths and a fixed bandwidth. The designated light corresponding to the second transmission mode includes two bandwidths, a fixed center wavelength.

Alternatively, as shown in fig. 1 and fig. 3, the tunable filter 110 is disposed directly above the single-channel photosensitive element 120, and in one duty cycle, the tunable filter 110 can transmit light with different central wavelengths at different times, so as to achieve multiple light detection. The tunable filter 110 can modulate the wavelength and the bandwidth of the designated light, so that the tunable filter 110 has high freedom of selection and a wider application range.

Further, as shown in fig. 2, tunable filter 110 includes a liquid crystal tunable color filter and the driver includes a driver circuit.

Further, the driver switches the light transmission mode by adjusting the voltage applied to the tunable filter 110.

In this embodiment, the tunable filter 110 includes a liquid crystal tunable color filter, which is a light splitting device made according to the electrically controlled birefringence effect of liquid crystal, and has functions of light modulation, deflection, and light filtering. The driving element comprises a driving circuit, wherein the driving element switches the light transmission mode by adjusting the voltage applied to the tunable filter 110, the control of the tunable filter 110 is simplified, the tunable filter 110 can be accurately switched in various light transmission modes only by the voltage, and the operation is simple and convenient and is easy to control.

Further, as shown in fig. 2, the tunable filter 110 includes a plurality of wave plates, which are stacked in the incident direction of the light. Wherein each of the plurality of wave plates includes a liquid crystal layer 111, a quartz layer 112, a polarizing plate 113, a first glass substrate 114, and a second glass substrate 115, and the quartz layer 112 is located at one side of the liquid crystal layer 111. A polarizer 113 is arranged on the side of the quartz layer 112 facing away from the liquid crystal layer 111. The first glass substrate 114 is provided between the liquid crystal layer 111 and the quartz layer 112. A second glass substrate 115 is provided on the side of the liquid crystal layer 111 facing away from the quartz layer 112.

In this embodiment, the liquid crystal layer 111 has a birefringence effect, which changes the refractive index of the o-light and the e-light, thereby changing the refractive index difference between the o-light and the e-light. Among them, light that complies with the ordinary law of refraction is called ordinary light (or o light), and light that does not comply with the ordinary law of refraction is called extraordinary light (or e light).

Δn＝n_o-n_e (1)

Δδ＝2πΔnd/λ (2)

Wherein, Delta n is the refractive index difference generated after the liquid crystal electric control double refraction effect, Delta delta is the phase difference generated after the liquid crystal electric control double refraction effect, n_oIs the refractive index of o light, n_eTo e the refractive index of light, λ denotes the wavelength of light in vacuum, and n denotes the refractive index of the medium.

Since the tunable filter 110 includes a plurality of waveplates, the plurality of waveplate units are cascaded to form a waveplate riot waveplate. As shown in fig. 2, a single set of wave plates includes a polarizer 113, a liquid crystal layer 111, and quartz, and forms a phase retarder.

From the birefringence effect, when natural light passes through the wave plate, the phase retardation generated by the o-light and the e-light is:

δ＝2πΓ_{general assembly}/λ (3)

In the formula, Γ ═ d Δ n represents the optical path length difference between o and e light, and therefore, for a single set of wave plates:

Γ_{general assembly}＝Γ_{Liquid crystal display device}+Γ_Quartz (4)

The spectral transmittance is:

T₁＝I₁/I₀＝0.5(1+cosδ)＝0.5[1+cos(2πΔnd/λ)] (5)

thus, for a plurality of waveplates, Γ_n+1＝2Γ_nThat is, the optical path difference of any one wave plate in the structure is twice as large as the optical path difference of the previous unit, wherein the spectral transmittance of light passing through the first wave plate is as follows:

T₁＝I₁/I₀＝0.5(1+cosδ)＝0.5[1+cos(2πΔnd/λ)] (6)

in the formula, I is a proper light intensity because of gamma_n+1＝2Γ_nThen for the other wave plates:

T₂＝I₂/I₁＝0.5(1+cos2δ) (7)

T₃＝I₃/I₂＝0.5(1+cos4δ) (8)

in the same way, T can be obtained₄、T₅、T₆And so on.

Wherein the content of the first and second substances,

T_{general assembly}＝T₁×T₂×T₃×...T_n (9)

When T is 1, that is, m λ is Δ nd (m is an integer), a wavelength band having a wavelength at λ is selected and output. Thus, tunable filter 110 enables electronically controlled tuning over a wide band. The phase of the wavelength is modulated respectively by changing the voltage applied to the liquid crystal layer 111, the output range of the waveband is selected, and other wavelengths are locked, so that the dynamic modulation of the tunable filter 110 is realized, high-precision narrow-wave output is obtained, the tunable filter 110 has no moving part, and has the advantages of large aperture, large viewing angle, good optical characteristics, simple control, small modulation voltage, continuous adjustment in a certain waveband range and the like.

It should be noted that, due to the light transmission characteristic of the tunable filter 110, the tunable filter 110 is matched with the single-channel photosensitive element 120, that is, a single wide-spectrum photodiode, so that an optical sensor with a wide spectrum range from visible light to near-infrared light, an arbitrary center wavelength, and an arbitrary bandwidth can be formed, and the sensing capability of forming light by unusual spectral components can be realized to meet some special requirements, for example, the combined light of red light and green light.

In addition, the tunable filter 110 can be applied to a color filter layer of a screen display panel in a screen assembly, so that the area can be saved, and the possibility of arranging larger pixel units in the same area can be explored.

Further, the number of the driving members is plural, and the plural driving members are connected to the liquid crystal layers 111 in the plural wave plates in a one-to-one correspondence manner.

In this embodiment, the number of the driving members is plural, the plural driving members are respectively connected to the liquid crystal layer 111 in each wave plate, and each driving member can control the liquid crystal layer 111 corresponding to the driving member, so as to provide a corresponding voltage to the liquid crystal layer 111 of each wave plate. The wave plates interfere and strengthen in a certain wave band range to obtain output, and cancel out in other wave band ranges to be locked. The voltage applied to the liquid crystal layer 111 is changed, so as to change the output wavelength band, thereby achieving the purpose that the liquid crystal tunable color filter outputs in different wavelength bands, and further enabling the tunable filter 110 to have a plurality of different light transmission modes.

Further, the tunable filter 110 is located directly above the single-channel photosensitive element.

In this embodiment, after the light is emitted to the tunable filter 110, the light can be transmitted to the photosensitive element as far as possible, so as to prevent the light from escaping due to the misaligned installation of the tunable filter 110 and the single-channel photosensitive element, or to prevent the light entering amount of the single-channel photosensitive element from being limited.

Further, the single-channel light sensing element 120 includes a photodiode or a phototransistor.

In this embodiment, the single-channel light sensing element 120 includes a photodiode or a phototransistor to achieve conversion of an optical signal to an electrical signal. The single channel light sensing element 120 can sense light intensity over a wide spectral range of visible light to achieve conversion of light into electricity. The single-channel photosensitive element 120 is matched with the tunable filter 110 to replace an array type multi-channel sensor, so that the problem that the field angles of a plurality of photodiodes or phototriodes in the multi-channel sensor are inconsistent is solved, and the consistency of multi-spectral sensing is improved. Meanwhile, on the basis of realizing multispectral sensing, the space occupation can be further saved, and the method can be applied to extremely narrow spaces.

According to some embodiments of the present application, there is provided a camera module, which includes a lens and the optical sensor mentioned in the above embodiments of the first aspect, wherein the optical sensor is disposed on a backlight side of the lens.

In this embodiment, the camera module includes a lens and an optical sensor, the optical sensor is disposed on a backlight side of the lens, external light passes through the lens and is emitted to the optical sensor, and under the action of the optical sensor, light of multiple colors can be recognized. The optical sensor may be equivalent to a color filter layer of a camera module in the related art.

According to some embodiments of the present application, there is provided an electronic device 200, which includes the optical sensor mentioned in the above embodiments of the first aspect, and further includes a housing assembly, the housing assembly having a receiving cavity and a light channel communicating with each other, at least a portion of the optical sensor being disposed in the receiving cavity corresponding to the light channel.

In this embodiment, the electronic device 200 includes the optical sensor provided in any of the above embodiments, and therefore has all the advantages of the optical sensor, which are not described herein.

Specifically, the casing subassembly includes back lid, framework and display screen, and the three encloses to close and forms and hold the chamber, and the gap between display screen and the framework constitutes light passage, and optical sensor establishes and holds the intracavity. Because the optical channel is comparatively narrow and small, and the space in the accommodating cavity is limited, the optical sensor with smaller occupied space is arranged, and therefore the overall layout of the electronic equipment can be optimized.

Further, as shown in fig. 1, the electronic device 200 includes a processor 210, the processor 210 is connected to the optical sensor, the processor 210 is configured to control the tunable filter 110 of the optical sensor to sequentially operate a plurality of light transmission modes, and the single-channel light sensing element 120 collects light data corresponding to each light transmission mode.

In this embodiment, the electronic device 200 further includes a processor 210, the processor 210 is connected to the optical sensor, and the processor 210 can control the tunable filter 110 and the single-channel photosensitive element 120 in the optical sensor to work together. Specifically, processor 210 can control tunable filter 110 to sequentially operate a plurality of light transmission modes, for example, when tunable filter 110 has at least one duty cycle, where a duty cycle is divided into 5 equal-length time segments (a first time segment, a second time segment, etc.). During the first time period, the processor 210 controls the tunable filter 110 to switch to the first light transmission mode, in which the tunable filter 110 can pass red light, that is, during the first time period, the optical sensor is equivalent to an R-channel photodiode. Similarly, the tunable filter 110 may be sequentially controlled to switch to the corresponding transmission modes in the second period to the fifth period, so as to allow green light, blue light, infrared light, and wide spectrum light to pass through. Also, in these periods, the optical sensor is equivalent to a single G-channel photodiode, a single B-channel photodiode, a single I-channel photodiode, and a single W-channel photodiode, respectively. Specifically, as shown in fig. 1, in one duty cycle, the processor 210 sequentially controls the tunable filter 110 to switch in the 5-pass mode in 5 time periods, and at the same time, the single-channel light sensing element 120 can collect light data in each time period. Further, the next cycle may be entered after the end of one cycle.

Further, when tunable filter 110 is a liquid crystal tunable filter, the bandwidth of the liquid crystal tunable filter can be controlled to a small value (e.g., 1nm), and then the bandwidth can be locked by varying the center wavelength within a certain range. For example, 1nm is spaced between 380nm and 1500nm, each central wavelength stays for a short time, at least the period of the single-channel photosensitive element 120 is collected in sequence, and light data is collected synchronously, so that a spectral curve of target light can be obtained after a working period, that is, a satellite spectrometer can be formed by the combination of the liquid crystal adjustable color filter and the single wide-spectrum photodiode, and the satellite spectrometer has spectrum detection capability.

Further, as shown in fig. 3, the electronic device 200 includes a light guide 230, and the light guide 230 is disposed in the light channel 221 and located on the light incident side of the optical sensor.

In this embodiment, when the electronic device 200 is a mobile phone, the optical sensor is often hidden under the micro-slit or the small hole due to the requirement of high screen ratio in a full-screen mobile phone. The housing 220 of the electronic device 200 forms an elongated channel (light channel 221), the optical sensor is disposed below the light channel 221, and external light is incident from the housing 220, passes through the elongated channel, and finally reaches the light-sensing surface of the optical sensor. By disposing the light guide 230 on the light incident side of the optical sensor, a stable light conduction path can be provided for the optical sensor, and the ambient light is emitted to the light guide 230 through the light channel 221, and then reaches the receiving end of the optical sensor (i.e., the tunable filter 110) through the light guide 230.

Further, the light incident end of the light guide 230 extends to the entrance of the light channel.

In this embodiment, the light incident end of the light guide 230 extends to the entrance of the light channel 221. That is, in the limited space of the light channel, the light guide member 230 is disposed as much as possible, and the external environment light can contact with the light guide member 230 at the entrance of the light channel, so that the light is refracted, reflected, and the like, and the external environment light can be sufficiently transmitted.

In the description herein, reference to the description of the terms "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples" or the like means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the application. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

While embodiments of the present application have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the application, the scope of which is defined by the claims and their equivalents.