DETECTOR FOR AN OPTICAL DETECTION OF AT LEAST ONE OBJECT

Abstract

Disclosed herein is a detector including (i) a transversal optical sensor adapted to determine a transversal position of a light beam traveling from the object to the detector, wherein the transversal optical sensor has a photosensitive layer embedded between at least two conductive layers such that at least one of the conductive layers contains an at least partially transparent graphene layer on an at least partially transparent substrate, and wherein the transversal optical sensor generates a transversal sensor signal indicative of the transversal position of the light beam in the photosensitive layer, and (ii) an evaluation device designed to generate at least one item of information on a transversal position of the object by evaluating the at least one transversal sensor signal.

Claims

1. A detector for an optical detection of at least one object (112), the detector comprising: at least one transversal optical sensor, the transversal optical sensor being adapted to determine a transversal position of a light beam traveling from the object to the detector, wherein the transversal position is a position in at least one dimension perpendicular to an optical axis of the detector, wherein the transversal optical sensor has at least one photosensitive layer embedded between at least two conductive layers, wherein at least one of the conductive layers comprises an at least partially transparent graphene layer deposited on an at least partially transparent substrate allowing the light beam to travel to the photosensitive layer wherein the transversal optical sensor is further adapted to generate at least one transversal sensor signal indicative of the transversal position of the light beam in the photosensitive layer; and at least one evaluation device, wherein the evaluation device is designed to generate at least one item of information on a transversal position of the object by evaluating the at least one transversal sensor signal.

2. The detector according to claim 1, wherein the graphene layer (134) exhibits an electrical sheet resistance of 100 /sq to 20 000 /sq.

3. The detector according to claim 1, wherein the graphene layer is at least partially transparent in a partition of a spectral range of 380 m to 1000 m.

4. The detector according to claim 3, wherein the graphene layer exhibits a transmission above 80% in a spectral range of 1 m to 3 m.

5. The detector according to claim 4, wherein the substrate carrying the graphene layer is at least partially transparent in a partition of the visible spectral range and/or in the infrared spectral range.

6. The detector according to claim 5, wherein the substrate comprises a material selected from the group consisting of quartz glass, sapphire, fused silica, silicon, germanium, zinc selenide, zinc sulfide, silicon carbide, aluminum oxide, calcium fluoride, magnesium fluoride, sodium chloride, and potassium bromide.

7. The detector according to claim 1, wherein the photosensitive layer comprises an inorganic photovoltaic material, an organic photovoltaic material, an inorganic photoconductive material, an organic photoconductive material, or a plurality of colloidal quantum dots (CQD) comprising an inorganic photovoltaic material or an inorganic photoconductive material.

8. The detector according to claim 7, wherein the inorganic photovoltaic material is at least one selected from the group consisting of a group II-VI compound, a group III-V compound, a group IV element or compound, a combination, a solid solution thereof, and a doped variant thereof.

9. The detector according to claim 8, wherein the group II-VI compound is a chalcogenide, wherein the chalcogenide is selected from the group consisting of: lead sulfide (PbS), lead selenide (PbSe), lead sulfoselenide (PbSSe), lead telluride (PbTe), copper indium sulfide (CIS), copper indium gallium selenide (CIGS), copper zinc tin sulfide (CZTS), copper zinc tin selenide (CZTSe), copper-zinc-tin sulfur-selenium (CZTSSe), cadmium telluride (CdTe), a solid solution thereof, and a doped variant thereof.

10. The detector according to claim 8, wherein the group IV element or compound is selected from a group consisting of doped diamond (C), doped silicon (Si), silicon carbide (SiC), silicon germanium (SiGe), and doped germanium (Ge), wherein the group IV element or compound is provided as a crystalline material, a microcrystalline material, and an amorphous material.

11. The detector according to claim 7, wherein the organic photovoltaic material comprises at least one electron donor material and at least one electron acceptor material, wherein the electron donor material is selected from the group consisting of poly(3-hexylthiophene-2,5.diyl) (P3HT), poly[3-(4-n-octyl)phenylthiophene] (POPT), poly[3-10-n-octyl-3-phenothiazine-vinylenethiophene-co-2,5-thiophene] (PTZV-PT), poly[4,8-bis[(2-ethylhexyl)oxy] benzo[1,2-b:4,5-b]dithiophene-2,6-diyl][3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophenediyl] (PTB7), poly {thiophene-2,5-diyl-alt-[5,6-bis(dodecyloxy)benzo[c][1,2,5]thiadiazole]-4,7-diyl} (PBT-T1), poly[2,6-(4,4-bis-(2-ethylhexyl)-4H-cyclopenta[2,1-b;3,4-b]dithiophene)-alt-4,7(2,1,3-benzothiadiazole)] (PCPDTBT), poly(5,7-bis(4-decanyl-2-thienyl)-thieno(3,4-b)diathiazolethiophene-2,5) (PDDTT), poly[N-9-heptadecanyl-2,7-carbazole-alt-5,5-(4,7-di-2-thienyl-2,1,3-benzothiadiazole)] (PCDTBT), poly[(4,4-bis(2-ethylhexyl)dithieno[3,2-b;2,3-d]silole)-2,6-diyl-alt-(2,1,3-benzothiadiazole)-4,7-diyl](PSBTBT), poly[3-phenylhydrazone thiophene] (PPHT), poly[2-methoxy-5-(2-ethylhexyl-oxy)-1,4-phenylenevinylene] (MEH-PPV), poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene-1,2-ethenylene-2,5-dimethoxy-1,4-phenylene-1,2-ethenylene] (M3EH-PPV), poly[2-methoxy-5-(3,7-dimethyloctyloxy)-1,4-phenylenevinylene] (MDMO-PPV), poly[9,9-di-octylfluorene-co-bis-N,N-4-butylphenyl-bis-N,N-phenyl-1,4-phenylenediamine](PFB), or a derivative, a modification, or a mixture thereof, and wherein the electron acceptor material is selected from [6,6]-phenyl-C61-butyric acid methyl ester (PCBM), [6,6]-Phenyl-C71-butyric acid methyl ester (PC70BM), [6,6]-phenyl C84 butyric acid methyl ester (PC84BM), an indene-C60 bisadduct (ICBA), cyano-poly[phenylenevinylene] (CN-PPV), poly[5-(2-(ethylhexyloxy)-2-methoxycyano-terephthalyliden] (MEH-CN-PPV), poly[oxa-1,4-phenylene-1,2-(1-cyano)-ethylene-2,5-dioctyloxy-1,4-phenylene-1,2-(2-cyano)-ethylene-1,4-phenylene] (CN-ether-PPV), poly[1,4-dioctyloxyl-p-2,5-dicyanophenylenevinylene](DOCN-PPV), poly[9,9-dioctyl-fluoreneco-benzothiadiazole] (PF8BT), a derivative thereof, a modification thereof, and a mixture thereof.

12. The detector according to claim 1, further comprising: a hole transporting layer, wherein the hole transporting layer comprises an electrically conducting polymer.

13. The detector according to claim 1, wherein the transversal optical sensor further has at least one split electrode located at one of the conductive layers, wherein the split electrode has at least two partial electrodes adapted to generate at least one transversal sensor signal.

14. The detector according to claim 1, wherein electrical currents through the partial electrodes are dependent on a position of the light beam in the photosensitive layer, wherein the transversal optical sensor is adapted to generate the transversal sensor signal in accordance with the electrical currents through the partial electrodes, wherein the detector is adapted to derive the information on the transversal position of the object from at least one ratio of the currents through the partial electrodes.

15. The detector according to claim 1, wherein the evaluation device is further designed to generate at least one item of information on a longitudinal position of the object by evaluating the transversal sensor signal of the longitudinal optical sensor in a different manner.

16. A method for an optical detection of at least one object, the method comprising: generating at least one transversal sensor signal by using at least one transversal optical sensor, the transversal optical sensor being adapted to determine a transversal position of a light beam traveling from the object to the detector, wherein the transversal position is a position in at least one dimension perpendicular to an optical axis of the detector, wherein the transversal optical sensor has at least one photosensitive layer embedded between at least two conductive layers, wherein at least one of the conductive layers comprises an at least partially transparent graphene layer on an at least partially transparent substrate allowing the light beam to travel to the photosensitive layer wherein the transversal optical sensor is further adapted to generate at least one transversal sensor signal indicative of the transversal position of the light beam in the photosensitive layer; and generating at least one item of information on a transversal position of the object by evaluating the at least one transversal sensor signal.

17. The detector according to claim 1, which is adapted to function as a detector for at least one application selected from the group consisting of a position measurement in traffic technology; an entertainment application; a security application; a human-machine interface application; a tracking application; a scanning application; a photography application; a cartography application; a mapping application for generating maps of at least one space; a homing or tracking beacon detector for vehicles; a mobile application; a webcam; an audio device; a Dolby surround audio system; a computer peripheral device; a gaming application; a camera (202) or video application; a surveillance application; an automotive application; a transport application; a logistics application; a vehicle application; an airplane application; a ship application; a spacecraft application; a robotic application; a medical application; a sports' application; a building application; a construction application; a manufacturing application; a machine vision application; a use in combination with at least one sensing technology selected from time-of-flight detector, radar, Lidar, ultrasonic sensors, and interferometry.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0279] Further optional details and features of the invention are evident from the description of preferred exemplary embodiments which follows in conjunction with the dependent claims. In this context, the particular features may be implemented alone or with features in combination. The invention is not restricted to the exemplary embodiments. The exemplary embodiments are shown schematically in the figures. Identical reference numerals in the individual figures refer to identical elements or elements with identical function, or elements which correspond to one another with regard to their functions.

[0280] Specifically, in the figures:

[0281] FIG. 1 shows an exemplary embodiment of a detector according to the present invention comprising a transversal optical sensor, wherein the transversal optical sensor has a transparent conductive layer comprising graphene;

[0282] FIG. 2 shows exemplary embodiments for the setup of the transversal optical sensor, wherein the photosensitive layer comprises an organic photovoltaic material (FIG. 2A), or a plurality of colloidal quantum dots (CQD) comprising an inorganic photoconductive material (FIG. 2B), respectively;

[0283] FIG. 3 shows experimental results which demonstrate the applicability of the transversal optical sensor according to FIGS. 1 and 2A as a position sensitive device (FIG. 3A) and a transmission curve of graphene on quartz glass in a partition of the Mid IR spectral range of 1 m to 3 m (FIG. 3B); and

[0284] FIG. 4 shows an exemplary embodiment of an optical detector, a detector system, a human-machine interface, an entertainment device, a tracking system and a camera according to the present invention.

EXEMPLARY EMBODIMENTS

[0285] FIG. 1 illustrates, in a highly schematic fashion, an exemplary embodiment of an optical detector 110 according to the present invention, for determining a lateral position of at least one object 112. The optical detector 110 may preferably be adapted to be used as a detector for a partition of the visible spectral range of 380 nm to 760 nm and/or the infrared spectral range of above 760 nm to 1000 m, particularly for wavelengths in a spectral range of 380 nm to 15 m, preferably of 380 nm to 3 m, specifically of 1 m to 3 m. As shown below in FIG. 3B in more detail, the graphene layer 134 may, particularly preferred, exhibit a transmission of at least 80% over a wavelength range of 1 m to 3 m. However, other embodiments may also be feasible.

[0286] The optical detector 110 comprises at least one transversal optical sensor 114, which, in this particular embodiment, may be arranged along an optical axis 116 of the detector 110. Specifically, the optical axis 116 may be an axis of symmetry and/or rotation of the setup of the optical sensors 114. As described elsewhere in this document, the transversal optical sensor 114 may, in a particularly preferred embodiment, concurrently be employed as longitudinal optical sensor adapted for determining a longitudinal position of the at least one object 112. Herein, the transversal optical sensor 114 may be located inside a housing 118 of the detector 110. Further, at least one transfer device 120 may be comprised, preferably a refractive lens 122. An opening 124 in the housing 118, which may, particularly, be located concentrically with regard to the optical axis 116, may preferably define a direction of view 126 of the detector 110. A coordinate system 128 may be defined, in which a direction parallel or antiparallel to the optical axis 116 is defined as a longitudinal direction, whereas directions perpendicular to the optical axis 116 may be defined as transversal directions. In the coordinate system 128 as symbolically depicted in FIG. 1 a longitudinal direction is denoted by z while transversal directions are denoted by x and y, respectively. However, other types of coordinate systems 128 are conceivable.

[0287] Further, the transversal optical sensor 114 in this embodiment has a photosensitive layer 130 which is located between two conductive layers i.e. a first conductive layer 132 and a second conductive layer 132. As described above and/or below in more detail, the photosensitive layer 130 may comprise an inorganic photovoltaic material, an organic photovoltaic material, an inorganic photoconductive material, an organic photoconductive material, or a plurality of quantum dots, in particular, a plurality of colloidal quantum dots (CQD), comprising an inorganic photovoltaic material or an inorganic photoconductive material. Herein, the first conductive layer 132 comprises an at least partially transparent graphene layer 134 deposited on an at least partially transparent substrate 135. Since the first conductive layer 132 is, therefore, at least partially optically transparent, it may, preferably, be located along the optical axis 116 of the optical detector 110 in a fashion that an incident light beam 136 may first traverse the first conductive layer 132 before it may impinge on the photosensitive layer 130.

[0288] In order to generate at least one transversal sensor signal which may be indicative of the transversal position of the light beam 136 within the photosensitive layer 130, the transversal optical sensor 114 is equipped with a split electrode which may, in the embodiment as depicted in FIG. 1, be located at the second conductive layer 132. However, other kinds of setups may also be conceivable. The transversal sensor signal may, preferably, be selected from the group consisting of a current and a voltage or any signal derived thereof. As schematically illustrated in FIG. 1, the split electrode has at least two partial electrodes 138, 138 which may, in particular, be arranged in a fashion that currents through the partial electrodes 138, 138 may depend on a position of the light beam 136 within the photosensitive layer 130. This kind of dependency can, in general, be achieved by Ohmic or resistive losses that may occur on a way from a location of a generation and/or modification of electrical charge carriers in the photosensitive layer 130 to the partial electrodes 138, 138. For this purpose, the graphene layer 134 may exhibit an electrical sheet resistance of 100 /sq to 20000 /sq, preferably of 100 /sq to 10 000 /sq, more preferred 125 of /sq to 1000 /sq, specifically of 150 of /sq to 500 /sq, thus, having a higher electrical resistance compared to the electrical resistance of the photosensitive layer 130 and, concurrently, and a lower electrical resistance compared to the partial electrodes 138, 138, thus, being adapted for guiding a current always along a path with the lowest Ohmic losses, respectively.

[0289] The evaluation device 140 is, generally, designed to generate at least one item of information on a position of the object 112 by evaluating the sensor signal of the transversal optical sensor 114. For this purpose, the evaluation device 140 may comprise one or more electronic devices and/or one or more software components, in order to evaluate the sensor signals, which are symbolically denoted by a transversal evaluation unit 142 (denoted by xy). As will be explained below in more detail, the evaluation device 140 may be adapted to determine the at least one item of information on the transversal position of the object 112 by comparing more than one transversal sensor signals of the transversal optical sensor 114.

[0290] Herein, the transversal sensor signal may be transmitted to the evaluation device 140 via one or more signal leads 144. By way of example, the signal leads 144 may be provided and/or one or more interfaces, which may be wireless interfaces and/or wire-bound interfaces. Further, the signal leads 144 may comprise one or more drivers and/or one or more measurement devices for generating sensor signals and/or for modifying sensor signals.

[0291] The light beam 136 for illumining the sensor region of the transversal optical sensor 114 may be generated by a light-emitting object 112. Alternatively or in addition, the light beam 136 may be generated by a separate illumination source 146, which may include an ambient light source and/or an artificial light source, such as a laser diode 148, being adapted to illuminate the object 112 that the object 112 may be able to reflect at least a part of the light generated by the illumination source 146 in a manner that the light beam 136 may be configured to reach the sensor region of the transversal optical sensor 114, preferably by entering the housing 118 of the optical detector 110 through the opening 124 along the optical axis 116.

[0292] In a specific embodiment, the illumination source 146 may be a modulated light source 150, wherein one or more modulation properties of the illumination source 146 may be controlled by at least one optional modulation device 152. Alternatively or in addition, the modulation may be effected in a beam path between the illumination source 146 and the object 112 and/or between the object 112 and the transversal optical sensor 114. Further possibilities may be conceivable. This specific embodiment may allow distinguishing different light beams 136 by taking into account one or more of the modulation properties, in particular the modulation frequency, when evaluating the transversal sensor signal of the transversal optical sensor 114 for determining the at least one item of information on the position of the object 112.

[0293] Generally, the evaluation device 140 may be part of a data processing device 154 and/or may comprise one or more data processing devices 154. The evaluation device 140 may be fully or partially integrated into the housing 118 and/or may fully or partially be embodied as a separate device which is electrically connected in a wireless or wire-bound fashion to the transversal optical sensor 114. The evaluation device 140 may further comprise one or more additional components, such as one or more electronic hardware components and/or one or more software components, such as one or more measurement units and/or one or more evaluation units and/or one or more controlling units (not depicted here).

[0294] FIG. 2A shows an exemplary embodiment for the setup of the transversal optical sensor 114, wherein, in this particular example, the photosensitive layer 130 may comprise an organic photovoltaic material 156, in particular P3HT:PCBM. As described above in more detail, the organic photovoltaic material 156 comprises poly(3-hexylthiophene-2,5.diyl) (P3HT) as electron donor material and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) as electron acceptor material, wherein the electron donor material and the electron acceptor material may constitute an interpenetrating network of donor and acceptor domains within the photosensitive layer 130. However, other kinds of substances available for the organic photovoltaic material 156 may also be applicable, in particular, other kinds of electron donor materials and/or electron acceptor materials.

[0295] Particularly, in order to achieve the desired high transmission through the first conductive layer 132, the substrate 135 carrying the graphene layer can, as schematically depicted in FIG. 2A, preferably, be selected from quartz glass 158, quartz glass, sapphire, fused silica, silicon, germanium, zinc selenide, zinc sulfide, silicon carbide, aluminum oxide, calcium fluoride, magnesium fluoride, sodium chloride, or potassium bromide.

[0296] As a result, the substrate 135 may at least be partially transparent in the visible spectral range and/or in the infrared spectral range, in particular within the same wavelength range of 380 nm to 3 m in which the graphene, as depicted in FIG. 3B below, exhibits a transmission above 80%. It may be noted that this property turns out to be in contrast to other typically used partially transparent materials, such as indium tin oxide (ITO) or fluorine-doped tin oxide (SnO.sub.2:F; FTO), which exhibit a low transmission within the IR spectral range and may, therefore, not particularly be suited for application in the first conductive layer 132 in the present invention. However, ITO, FTO, or other transparent conducting oxides (TCO) can still be used for the second conductive layer 132 although, as shown in FIG. 2A, the second conductive layer 132 may, depending on the path of the light beam 136, also comprise an at least partially intransparent material, preferably, a metal sheet or a low-resistive graphene sheet, wherein the metal sheet may comprise one or more of silver, copper, aluminum, platinum, magnesium, chromium, titanium, or gold, and wherein the low-resistive graphene sheet may have an electrical sheet resistance below 100 /sq, preferably of 1 /sq or below.

[0297] As further depicted in FIG. 2A, the transversal optical sensor 114 may, additionally, comprise a hole transporting layer 160. For this purpose, an electrically conducting polymer 162 which may, in particular, be selected from poly(3,4-ethylenedioxythiophene) (PEDOT) or a dispersion of PEDOT and a polystyrene sulfonic acid (PEDOT:PSS) may, preferably, be used. However other kinds of materials for the hole transporting layer 160 may also be feasible. As generally used, the hole transporting layer 160 may, preferably, be adapted to facilitate a transport of the holes on a way through the transversal optical sensor 114. Alternatively, an electron transporting layer (not depicted here) may also be applicable for the present purpose.

[0298] As a result, the particular embodiment of the transversal optical sensor 114 as shown in FIG. 2A the may also be denominated as a photodiode. In contrast hereto, FIG. 2B illustrates an alternative embodiment of the transversal optical sensor 114 in which the photosensitive layer 130 may be provided in form of a colloidal film 164 which may comprise a plurality of quantum dots 166. As particularly preferred, the quantum dots 166 may comprise nanometer-scale crystals of lead sulfide (PbS) or lead selenide (PbSe), wherein other chalcogenides such as lead sulfoselenide (PbSSe), lead telluride (PbTe), copper indium sulfide (CIS), copper indium gallium selenide (CIGS), copper zinc tin sulfide (CZTS), copper zinc tin selenide (CZTSe), copper-zinc-tin sulfur-selenium (CZTSSe), or cadmium telluride (CdTe) may also be applicable for this purpose. Herein, the nanometer-scale crystals may exhibit a size from 1 nm to 100 nm, preferably from 2 nm to 100 nm, more preferred from 2 nm to 15 nm, while the colloidal film 164 may exhibit a thickness of 1 nm to 100 nm, preferably of 2 nm to 100 nm, more preferred of 2 nm to 15 nm, wherein, however, the sizes of the quantum dots 166 may be selected in a fashion that their size remains below the thickness of the colloidal film 164.

[0299] In the embodiment of the transversal optical sensor 114 as schematically illustrated in FIG. 2B, the colloidal film 164 of the sub-micrometer-scale crystals of PbS which constitutes the photosensitive layer 130 is sandwiched between the first conductive layer 132 and the second conductive layer 132. According to the present invention, the first conductive layer 132 which is traversed by the incident light beam 136 comprises, as described above in more detail, the graphene layer 134 deposited on the at least partially optically transparent substrate 135, preferably, selected from quartz glass 158 or aluminum oxide.

[0300] Further, the second conductive layer 132 may comprise the electrically conducting polymer 162, preferably, poly(3,4-ethylenedioxythiophene) (PEDOT) or a dispersion of PEDOT and a polystyrene sulfonic acid (PEDOT:PSS), which may be deposited onto the colloidal film 164. In order to achieve a good electrical contact to outside electrical connections, a split electrode comprising the at last two evaporated 200 nm silver (Ag) partial electrodes 138, 138 have been deposited on second conductive layer 132. Herein, the layer of the electrically conducting polymer 162 may, preferably, exhibit an electrical sheet resistance of 100 /sq to 20 000 /sq, more preferred of 1000 /sq to 15000 /sq, more preferred of 2000 /sq to 10000 /sq. Alternatively, the split electrode may be selected from the group comprising silver, copper, aluminum, platinum, magnesium, chromium, titanium, gold, or low-resistive graphene as described above. Herein, the split electrode may, preferably be arranged as a number of partial electrodes 138, 138 or in form of a metallic grid.

[0301] Further, a hole blocking layer 168 which, preferably, comprises a titanium dioxide (TiO.sub.2) layer 170, may be deposited onto the first conductive layer 132 before the colloidal film 164 may be deposited on top of the hole blocking 168 layer. In the particular embodiment of FIG. 2B, the titanium dioxide layer 170 may be an n-type semiconductor and may comprise titanium dioxide (TiO.sub.2) particles. Alternatively, the hole blocking layer 168 could also comprise zinc oxide (ZnO) or, wherein the blocking layer is a p-type semiconductor, molybdenum oxide (MoO.sub.3). Herein, the hole blocking layer 168 comprising the TiO.sub.2 may, in particular, block a transport of electrons, whereby a recombination between holes and electrons within the hole blocking layer 168 may be excluded.

[0302] FIG. 3A shows experimental results which demonstrate the applicability of the transversal optical sensor 114 according to FIGS. 1 and 2A for this purpose. Herein, the transversal optical sensor 114 comprising the setup as schematically depicted in FIG. 2A, has been illuminated by a laser diode 148 emitting a wavelength of 530 nm at an applied current of 1000 mA. Herein, a distance between the laser diode 148 and the transversal optical sensor 114 has been arranged to be about 23 cm while the distance between the laser diode 148 and the transfer device 120 was about 12 cm.

[0303] FIG. 3A schematically illustrates a sensor area 172 of the transversal optical sensor 114 in an x-direction and a y-direction, wherein the sensor area 172 as employed here has an active area of 1212 mm.sup.2. Herein, for a number of measurement points positions 174 as determined by application of the evaluation device 140 of the transversal optical sensor 114 according to the present invention have been compared with actual positions 176 which have been available by other kinds of methods, such as by employing geometrical considerations in using a known setup of the transversal optical sensor 114.

[0304] In order to determine a position 174 of a measurement point by application of transversal optical sensor 114, the following procedure may be used. By way of example (not depicted here), a split electrode comprising four partial electrodes being located on top of the four rims of the second conductive layer 132 which has a square or a rectangular form is employed. Herein, by generating and/or modifying charge carriers in the photosensitive layer 130, electrode currents may be obtained, which, in each case, may be denoted by i.sub.1, to i.sub.4. As used herein, electrode currents i.sub.1, i.sub.2 may denote electrode currents through the partial electrodes located in y-direction and electrode currents i.sub.3, i.sub.4 may denote electrode currents through the partial electrodes located in x-direction. The electrode currents may be measured by one or more appropriate electrode measurement devices simultaneously or sequentially. By evaluating these electrode currents, the desired x- and y-coordinates of the position 174 of the measurement point under investigation, i.e. x.sub.0 and y.sub.0, may be determined. Thus, the following equations may be used:

[00001]$x_0=f\left(\frac{i_3-i_4}{i_3+i_4}\right).Math..Math.\mathrm{and}.Math..Math.y_0=f\left(\frac{i_1-i_2}{i_1+i_2}\right).$

[0305] Herein, might be an arbitrary known function, such as a simple multiplication of the quotient of the currents with a known stretch factor and/or an addition of an offset. Thus, generally, the electrode currents i.sub.1 to i.sub.4 might provide transversal sensor signals generated by the transversal optical sensor 114, whereas the evaluation device 140 might be adapted to generate information on a transversal position, such as at least one x-coordinate and/or at least one y-coordinate, by transforming the transversal sensor signals by using a predetermined or determinable transformation algorithm and/or a known relationship.

[0306] The results as shown in FIG. 3A demonstrate that for the number of the measurement points as presented there, the positions 174 as determined by the application of the transversal optical sensor 114 according to the present invention are reasonably comparable with the actual positions 176 acquired by another kinds of method.

[0307] As already mentioned above, the transversal sensor 114 according to the present invention may concurrently be employed as a longitudinal optical sensor adapted for determining the z-position. For this purpose, a sum of the electrode currents i.sub.1, i.sub.2 through the partial electrodes located in y-direction and of the electrode currents i.sub.3, i.sub.4 through the partial electrodes located in x-direction may be used in a preferred embodiment, wherein the electrode currents may be measured by one or more appropriate electrode measurement devices simultaneously or sequentially, for determining the z-coordinate. By evaluating these electrode currents, the desired z-coordinate of the position 174 of the measurement point under investigation, i.e. z.sub.0, may be determined by using the following Equation:

z.sub.0=f(i.sub.1+i.sub.2+i.sub.3+i.sub.4)

[0308] For further details with respect to evaluating electrode currents in order to obtain the desired z-coordinate, reference may be made to WO 2012/110924 A1 or WO 2014/097181 A1.

[0309] FIG. 3B illustrates a transmission curve 178 of the graphene layer 134 on quartz glass 158 over a partition of the Mid IR spectral range from 1 m to 3 m after the transmission of the quartz glass 158 has been subtracted. As shown in FIG. 3B, it could be experimentally verified that the graphene layer 134 may exhibit a transmission above a threshold 180 of 80% in a wavelength range of 1 m to 3 m. In addition, N.-E. Weber et al., see above, disclose that, depending on details of the preparation, the graphene layer 134 may exhibit a transmission above a threshold 180 of 80% in a wavelength range of 380 nm to 800 nm provided that the graphene layer 134 may exhibit an electrical sheet resistance of at least approx. 2000 /sq. However, further experiments demonstrated that the graphene layer 134 having a lower sheet resistance of 100 /sq to 1000 /sq, preferably of 125 of /sq to 1000 /sq, specifically of 150 of /sq to 500 /sq resulted in an improved frequency response for the optical detector. Consequently, using this setup of the graphene layer 134 on the quartz glass 158 allows providing the first conductive layer 132 in a manner that it actually exhibits the desired high transmission above the threshold 180 of 80% over the partition of the Mid IR spectral range, in particular, of 1 m to 3 m.

[0310] As a further example, FIG. 4 shows an exemplary embodiment of a detector system 200, comprising at least one optical detector 110, wherein the optical detector 110 as disclosed in the embodiments as shown in FIGS. 1 and 2A is used. However, other kinds of optical sensors 110 according to the present invention may also be applicable. Herein, the optical detector 110 may be employed as a camera 202, specifically for 3D imaging, which may be made for acquiring images and/or image sequences, such as digital video clips. Further, FIG. 4 shows an exemplary embodiment of a human-machine interface 204, which comprises the at least one detector 110 and/or the at least one detector system 200, and, further, an exemplary embodiment of an entertainment device 206 comprising the human-machine interface 204. FIG. 4 further shows an embodiment of a tracking system 208 adapted for tracking a position of at least one object 112, which comprises the detector 110 and/or the detector system 200. With regard to the optical detector 110, reference may be made to the full disclosure of this application. Basically, all potential embodiments of the detector 110 may also be embodied in the embodiment shown in FIG. 4.

[0311] As described above, the optical detector 110 may comprise a single transversal optical sensor 114 or, as e.g. disclosed in WO 2014/097181 A1, one or more transversal optical sensors 114, particularly, in combination with one or more longitudinal optical sensors 209. In a particularly preferred embodiment, the transversal optical sensor 114 may concurrently be employed as one of the longitudinal optical sensors 209 as described above. Alternatively or in addition, one or more at least partially longitudinal transversal optical sensors 209 may be located on a side of the stack of transversal optical sensors 114 facing towards the object 112. Alternatively or additionally, one or more longitudinal optical sensors 209 may be located on a side of the stack of transversal optical sensors 114 facing away from the object 112. As described in WO 2014/097181 A1, a use of two or, preferably, three longitudinal optical sensors 209 may support the evaluation of the longitudinal sensor signals without any remaining ambiguity. However, embodiments which may only comprise a single transversal optical 114 sensor but no longitudinal optical sensor 209 may still be possible, such as in a case wherein only determining the x- and y-coordinates of the object may be desired. The at least one optional longitudinal optical sensor 209 may further be connected to the evaluation device 140, in particular, by the signal leads 144.

[0312] Further, the at least one transfer device 120 may be provided, in particular as the refractive lens 122 or convex mirror. The optical detector 110 may further comprise the at least one housing 118 which, as an example, may encase one or more of components 114, 209.

[0313] Further, the evaluation device 140 may fully or partially be integrated into the optical sensors 114, 209 and/or into other components of the optical detector 110. The evaluation device 140 may also be enclosed into housing 118 and/or into a separate housing. The evaluation device 140 may comprise one or more electronic devices and/or one or more software components, in order to evaluate the sensor signals, which are symbolically denoted by the transversal evaluation unit 142 (denoted by xy) and a longitudinal evaluation unit 210 (denoted by z). By combining results derived by these evolution units 142, 210, a position information 212, preferably a three-dimensional position information, may be generated (denoted by x, y, z).

[0314] Further, the optical detector 110 and/or to the detector system 200 may comprise an imaging device 214 which may be configured in various ways. Thus, as depicted in FIG. 4, the imaging device 214 can for example be part of the detector 110 within the detector housing 118. Herein, the imaging device signal may be transmitted by one or more imaging device signal leads 144 to the evaluation device 140 of the detector 110. Alternatively, the imaging device 214 may be separately located outside the detector housing 118. The imaging device 214 may be fully or partially transparent or intransparent. The imaging device 214 may be or may comprise an organic imaging device or an inorganic imaging device. Preferably, the imaging device 214 may comprise at least one matrix of pixels, wherein the matrix of pixels may particularly be selected from the group consisting of: an inorganic semiconductor sensor device such as a CCD chip and/or a CMOS chip; an organic semiconductor sensor device.

[0315] In the exemplary embodiment as shown in FIG. 4, the object 112 to be detected, as an example, may be designed as an article of sports equipment and/or may form a control element 216, the position and/or orientation of which may be manipulated by a user 218. Thus, generally, in the embodiment shown in FIG. 4 or in any other embodiment of the detector system 200, the human-machine interface 204, the entertainment device 206 or the tracking system 208, the object 112 itself may be part of the named devices and, specifically, may comprise the at least one control element 216, specifically, wherein the at least one control element 216 has one or more beacon devices 220, wherein a position and/or orientation of the control element 216 preferably may be manipulated by user 218. As an example, the object 112 may be or may comprise one or more of a bat, a racket, a club or any other article of sports equipment and/or fake sports equipment. Other types of objects 112 are possible. Further, the user 218 may be considered as the object 112, the position of which shall be detected. As an example, the user 218 may carry one or more of the beacon devices 220 attached directly or indirectly to his or her body.

[0316] The optical detector 110 may be adapted to determine at least one item on a transversal position of one or more of the beacon devices 220 and, optionally, at least one item of information regarding a longitudinal position thereof. Particularly, the optical detector 110 may be adapted for identifying colors and/or for imaging the object 112, such as different colors of the object 112, more particularly, the color of the beacon devices 220 which might comprise different colors. The opening 124 in the housing 118, which, preferably, may be located concentrically with regard to the optical axis 116 of the detector 110, may preferably define a direction of a view 126 of the optical detector 110.

[0317] The optical detector 110 may be adapted for determining the position of the at least one object 112. Additionally, the optical detector 110, specifically an embodiment including the camera 202, may be adapted for acquiring at least one image of the object 112, preferably a 2D- or a 3D-image. As outlined above, the determination of a position of the object 112 and/or a part thereof by using the optical detector 110 and/or the detector system 200 may be used for providing a human-machine interface 204, in order to provide at least one item of information to a machine 222. In the embodiments schematically depicted in FIG. 4, the machine 222 may be or may comprise at least one computer and/or a computer system comprising the data processing device 154. Other embodiments are feasible. The evaluation device 140 may be a computer and/or may comprise a computer and/or may fully or partially be embodied as a separate device and/or may fully or partially be integrated into the machine 222, particularly the computer. The same holds true for a track controller 224 of the tracking system 208, which may fully or partially form a part of the evaluation device 140 and/or the machine 222.

[0318] Similarly, as outlined above, the human-machine interface 204 may form part of the entertainment device 206. Thus, by means of the user 218 functioning as the object 112 and/or by means of the user 218 handling the object 112 and/or the control element 216 functioning as the object 112, the user 218 may input at least one item of information, such as at least one control command, into the machine 222, particularly the computer, thereby varying the entertainment function, such as controlling the course of a computer game.

LIST OF REFERENCE NUMBERS

[0319] 110 detector [0320] 112 object [0321] 114 transversal optical sensor [0322] 116 optical axis [0323] 118 housing [0324] 120 transfer device [0325] 122 refractive lens [0326] 124 opening [0327] 126 direction of view [0328] 128 coordinate system [0329] 130 photosensitive layer [0330] 132, 132 first conductive layer, second conductive layer [0331] 134 graphene layer [0332] 135 transparent substrate [0333] 136 light beam [0334] 138, 138, 138 partial electrode [0335] 140 evaluation device [0336] 142 transversal evaluation unit [0337] 144 signal leads [0338] 146 illumination source [0339] 148 laser diode [0340] 150 modulated illumination source [0341] 152 modulation device [0342] 154 data processing device [0343] 156 organic photovoltaic material [0344] 158 quartz glass [0345] 160 hole transporting layer [0346] 162 electrically conducting polymer [0347] 164 colloidal film [0348] 166 plurality of quantum dots [0349] 168 hole blocking layer [0350] 170 titanium dioxide layer [0351] 172 sensor area [0352] 174 determined position [0353] 176 actual position [0354] 178 sensor area [0355] 180 threshold [0356] 200 detector system [0357] 202 camera [0358] 204 human-machine interface [0359] 206 entertainment device [0360] 208 tracking system [0361] 209 longitudinal optical sensor [0362] 210 longitudinal evaluation unit [0363] 212 position information [0364] 214 imaging device [0365] 216 control element [0366] 218 user [0367] 220 beacon device [0368] 222 machine [0369] 224 track controller