DETECTOR FOR AN OPTICAL DETECTION OF AT LEAST ONE OBJECT

Abstract

Disclosed herein is a detector (110) for an optical detection of at least one object (112) the detector (110) including: (a) at least one longitudinal optical sensor (114) having at least one sensor region (130), the longitudinal optical sensor (114) containing at least one photodiode (134) the photodiode (134) having at least two electrodes (166, 174), wherein at least one photoactive layer (180) containing at least one electron donor material and at least one electron acceptor material is embedded between the electrodes (166, 174); and (b) at least one evaluation device (150) designed to generate at least one item of information on a longitudinal position of the object (112) by evaluating the longitudinal sensor signal. The detector (110) is efficient for accurately determining of a position of at least one object (112) in space, and exhibits an FiP effect with an improved signal-to-noise ratio.

Claims

1. A detector for optically detecting at least one object, comprising at least one longitudinal optical sensor, wherein the longitudinal optical sensor has at least one sensor region, wherein the longitudinal optical sensor is designed to generate at least one longitudinal sensor signal in a manner dependent on an illumination of the sensor region by the light beam, wherein the longitudinal sensor signal, given the same total power of the illumination, is dependent on a beam cross-section of the light beam in the sensor region, wherein the longitudinal optical sensor comprises at least one photodiode, the photodiode having at least two electrodes, wherein at least one photoactive layer comprising at least one electron donor material and at least one electron acceptor material is embedded between the electrodes; and at least one evaluation device, wherein the evaluation device is designed to generate at least one item of information on a longitudinal position of the object by evaluating the longitudinal sensor signal.

2. The detector according to claim 1, wherein the electron donor material comprises an organic donor polymer.

3. The detector according to claim 1, wherein the organic donor polymer is one 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-ethyl-hexyl)-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-benzothia-diazole)] (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-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV), poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene-1,2-ethenylene-2,5-dimethoxy-1,4- phenyene-1,2-ethenylene] (M3EH-PPV), poly[2-methoxy-5-(3,7-dimethyloctyloxy)-1,4-phenylene-vinylene] (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.

4. The detector according to claim 1, wherein the electron acceptor material comprises one of a fullerene-based electron acceptor material, tetracyanoquinodimethane (TCNQ), a perylene derivative, or inorganic nanoparticles.

5. The detector according to claim 4, wherein the fullerene-based electron acceptor material comprises one of [6,6]-phenyl-C61-butric acid methyl ester (PC60BM), [6,6]-Phenyl-C71-butyric acid methyl ester (PC70BM), [6,6]-phenyl C84 butyric acid methyl ester (PC84BM), an indene-C60 bisadduct (ICBA), a diphenylmethanofullerene (DPM) moiety comprising one or two attached oligoether (OE) chains (C70-DPM-OE or C70-DPM-OE2, respectively), or a Preliminary Amendment derivative, a modification, or a mixture thereof

6. The detector according to claim 1, any one of the preceding claims, wherein the electron acceptor material comprises an organic acceptor polymer.

7. The detector according to claim 6, wherein the organic acceptor polymer comprises one of a cyano-poly[phenylenevinylene] (CN-PPV), poly[5-(2-(ethylhexyloxy)-2-methoxycyanoterephthalyliden] (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-di-octylfluoreneco-benzothiadiazole] (PF8BT), or a derivative, a modification, or a mixture thereof.

8. The detector according to claim 1, wherein the electron donor material and the electron acceptor material comprise an interpenetrating network of donor and acceptor domains, interfacial areas between the donor and acceptor domains, and percolation pathways connecting the domains to the electrodes.

9. The detector according to claim 1, wherein at least one of the electrodes is at least partially optically transparent.

10. (canceled)

11. The detector according to claim 9, wherein an optically transparent substrate is at least partially covered with the at least partially optically transparent electrode.

12. The detector according to claim 1, wherein at least one of the electrodes is optically intransparent and comprises a metal electrode.

13. (canceled)

14. The detector according to claim 1, wherein the photoactive layer is embedded between two different kinds of charge-influencing layers, wherein the two different kinds of charge-influencing layers comprise, for the same kind of charge carriers, a charge-carrier blocking layer and a charge-carrier transporting layer or, for two different kinds of charge carriers, two different charge-carrier blocking layers or two different charge-carrier transporting layers.

15. The detector according to claim 12, wherein at least one of the charge-influencing layer is at least partially optically transparent and is located adjacent to the at least partially optically transparent electrode.

16. The detector according to claim 12, wherein the charge-carrier blocking layer is a hole blocking layer, wherein the hole blocking layer comprises one of cesium carbonate (Cs.sub.2CO.sub.3), polyethylenimine (PEI), polyethylenimine ethoxylate (PEIE), 2,9-dimethyl-4,7-diphenyl-phenanthroline (BCP), (3-(4-biphenylyl)-4-phenyl-5-(4-tent-butylphenyl)-12,4-triazole) (TAZ), a transition metal oxide, or an alkaline fluoride.

17. The detector according to claim 12, wherein the charge-carrier transporting layer is a hole transporting layer, wherein the hole transporting layer is selected from the group consisting of a poly-3,4-ethylenedioxythiophene (PEDOT), a poly-aniline (PANI), a polythiophene(PT), or wherein the charge-carrier blocking layer is an electron blocking layer selected from a molybdenum oxide or a nickel oxide.

18-19. (canceled)

20. The detector according to claim 1, further comprising: at least one transversal optical sensor, the transversal optical sensor being adapted to determine a transversal position of the light beam traveling from the object to the detector, the transversal position being a position in at least one dimension perpendicular an optical axis of the detector, the transversal optical sensor being adapted to generate at least one transversal sensor wherein the evaluation device is further designed to generate at least one item of information on a transversal position of the object by evaluating the transversal sensor signal.

21. The detector according to claim 1, wherein the detector furthermore has at least one modulation device for modulating the illumination, wherein the longitudinal optical sensor is furthermore designed in such a way that the longitudinal sensor signal, given the same total power of the illumination, is dependent on a modulation frequency of a modulation of the illumination.

22. The detector according to claim 1, furthermore comprising at least one of the group consisting of an illumination source, a transfer device, and an imaging device.

23-30. (canceled)

31. A method for an optical detection of at least one object, the method comprising: generating at least one longitudinal sensor signal by using at least one longitudinal optical sensor , wherein the longitudinal sensor signal is dependent on an illumination of a sensor region of the longitudinal optical sensor by a light beam, wherein the longitudinal sensor signal, given the same total power of the illumination, is dependent on a beam cross-section of the light beam in the sensor region, wherein the longitudinal optical sensor comprises at least one photodiode, the photodiode having at least two electrodes, wherein at least one photoactive layer comprising at least one electron donor material and at least one electron acceptor material is embedded between the electrodes; and evaluating the longitudinal sensor signal of the longitudinal optical sensor by determining an item of information on the longitudinal position of the object from the longitudinal sensor signal.

32. An article, comprising a detector according to claim 1, wherein the article is adapted to function as an article for an application selected from the group consisting of: a distance measurement, in particular in traffic technology; a position measurement, in particular in traffic technology; an entertainment application; a security application; a human-machine interface application; a tracking application; a logistics application; a machine vision application; a safety application; a surveillance application; a data collection application; a scanning application, a photography application; an imaging application or camera application; a mapping application for generating maps of at least one space.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0255] 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.

[0256] Specifically, in the figures:

[0257] FIG. 1 illustrates an exemplary embodiment of an optical detector according to the present invention comprising at least one longitudinal optical sensor;

[0258] FIG. 2 shows a particularly preferred embodiment of a photodiode comprised in a sensor region of the longitudinal optical sensor according to the present invention;

[0259] FIG. 3 shows an experimental diagram presenting the current density vs. voltage characteristics of the optical detector under illumination;

[0260] FIG. 4A and 4B depict the photocurrent vs. distance between the longitudinal optical sensor and the object (FIG. 4A) and the photocurrent vs. frequency of a modulation for different focus conditions (FIG. 4B); and

[0261] FIG. 5 shows an exemplary embodiment of the optical detector and of a detector system, a human-machine interface, an entertainment device, a tracking system, and a camera, each comprising the optical detector according to the present invention.

EXEMPLARY EMBODIMENTS

[0262] FIG. 1 illustrates, in a highly schematic illustration, an exemplary embodiment of an optical detector 110 according to the present invention, for determining a position of at least one object 112. However, other embodiments are feasible.

[0263] The optical detector 110 comprises at least one longitudinal optical sensor 114, which, in this particular embodiment, is 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. The optical sensors 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, preferably defines 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, symbolically depicted in FIG. 1, a longitudinal direction is denoted by z and transversal directions are denoted by x and y, respectively. However, other types of coordinate systems 128 are feasible.

[0264] Further, the longitudinal optical sensor 114 is designed to generate at least one longitudinal sensor signal in a manner dependent on an illumination of a sensor region 130 by a light beam 132. Thus, according to the FiP effect, the longitudinal sensor signal, given the same total power of the illumination, is dependent on a beam cross-section of the light beam 132 in the respective sensor region 130, as will be outlined in further detail below. According to the present invention, the sensor region 130 of the longitudinal optical 110 sensor comprises at least one photodiode 134, in particular in a preferred embodiment which is described in FIG. 2 in more detail.

[0265] The light beam 132 for illumining the sensor region 130 of the longitudinal optical sensor 114 may be generated by a light-emitting object 112. Alternatively or in addition, the light beam 132 may be generated by a separate illumination source 136, which may include an ambient light source and/or an artificial light source 138, such as a light-emitting diode 140, 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 136 in a manner that the light beam 132 may be configured to reach the sensor region 130 of the longitudinal optical sensor 114, preferably by entering the housing 118 of the optical detector 110 through the opening 124 along the optical axis 116.

[0266] In a specific embodiment, the illumination source 136 may be a modulated light source 142, wherein one or more modulation properties of the illumination source may be controlled by at least one modulation device 144. Alternatively or in addition, the modulation may be effected in a first beam path 146 between the illumination source and the object 112 and/or in a second beam path 148 between the object 112 and the longitudinal optical sensor 114. Further possibilities may be conceivable. In this specific embodiment, it may be advantageous taking into account one or more of the modulation properties, in particular the modulation frequency, when evaluating the sensor signal of the transversal optical sensor 114 for determining the at least one item of information on the position of the object 112.

[0267] The evaluation device 150 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 longitudinal optical sensor 114. For this purpose, the evaluation device 150 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 longitudinal evaluation unit 152 (denoted by z). As will be explained below in more detail, the evaluation device 150 may be adapted to determine the at least one item of information on the longitudinal position of the object 112 by comparing more than one longitudinal sensor signals of the longitudinal optical sensor 114. As explained above, the longitudinal sensor signal as provided by the longitudinal optical sensor 114 upon impingement by the light beam 132 depends on an illumination of the sensor region 130 by the light beam 132, wherein the longitudinal sensor signal, given the same total power of the illumination, is dependent on a beam cross-section of the light beam 132 in the sensor region 130. As for example explained in WO 2012/110924 A1 in more detail, the evaluation device 150 may be adapted to determine the at least one item of information on the longitudinal position of the object 112 by comparing more than one longitudinal sensor signals of the longitudinal optical sensor 114.

[0268] Generally, the evaluation device 150 may be part of a data processing device and/or may comprise one or more data processing devices. The evaluation device 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, such as via one or more signal leads 154, to the longitudinal optical sensor 114. The evaluation device 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 (not depicted in FIG. 1) and/or one or more controlling units, such as the modulation device 144 being adapted to control the modulation properties of the modulated light source 142. Further, the evaluation device 150 may be a computer 156 and/or may comprise a computer system comprising a data processing device 158. However, other embodiments are feasible.

[0269] In a preferred embodiment, the optical detector 110 further comprises at least one transversal optical sensor 160 which, in this particular embodiment, is also arranged along an optical axis 116 of the detector 110. Herein, the transversal optical sensor 160 may, preferably, be adapted to determine a transversal position of the light beam 132 traveling from the object 112 to the optical detector 110. Herein, the transversal position may be a position in at least one dimension perpendicular an optical axis 116 of the optical detector 110, in this particular embodiment denoted by x and y, respectively, according to the coordinate system 128. The transversal optical sensor 160 may further be adapted to generate at least one transversal sensor signal. The transversal sensor signal may be transmitted in a wireless or wire-bound fashion, such as via one or more signal leads 154, to the evaluation device 150, which may further be designed to generate at least one item of information on a transversal position of the object 112 by evaluating the transversal sensor signal. For this purpose, the evaluation device 150 may further 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 162 (denoted by z). Further, by combining results derived by the evolution units 152, 162, a position information 164, preferably a three-dimensional position information, symbolically denoted here by x, y, z, may thus be generated.

[0270] The optical detector 110 may have a straight beam path or a tilted beam path, an angulated beam path, a branched beam path, a deflected or split beam path or other types of beam paths. Further, the light beam 132 may propagate along each beam path or partial beam path once or repeatedly, unidirectionally or bidirectionally. Thereby, the components listed above or the optional further components listed in further detail below may fully or partially be located in front of the longitudinal optical sensors 114 and/or behind the longitudinal optical sensors 114.

[0271] FIG. 2 shows a particularly preferred embodiment of the photodiode 134 within the sensor region 130 of the longitudinal optical sensor 110 according to the present invention.

[0272] As schematically depicted, the photodiode 134 has an optically transparent first electrode 166. Preferably, the photodiode 134 may be arranged in a manner that the optically transparent first electrode 166 may be located towards the incident light beam 132. The optically transparent first electrode 166 may comprise a layer of one or more transparent conductive oxides 168 (TCO), in particular indium-doped tin oxide (ITO). However, other kinds of optically transparent materials, such as fluorine-doped tin oxide (FTO) or aluminum-doped zinc oxide (AZO), may also be suitable for this purpose. In order to be able to using a minimum of the optically transparent oxide 168 but still keep the optically transparent first electrode 166 mechanically stable, the optically transparent oxide 168 may be placed on top of an optically transparent substrate 170, in particular on top of a glass substrate 172, preferably by using a deposition method, such as a coating or an evaporation method. Alternatively, a quartz substrate or a substrate comprising an optically transparent but electrically insulating polymer, such as poly-3,4-ethylenedioxythiophene (PEDOT) or polyethylene terephthalate (PET), may also be used for this purpose.

[0273] Further, the photodiode 134 has a second electrode 174, which may be optically intransparent. Accordingly, the photodiode 134 may be arranged in a manner that the optically intransparent second electrode 174 may be located away from the incident light beam 132. In this preferred embodiment, the second electrode 174 may comprise a metal electrode 176, such as a silver (Ag) electrode, a platinum (Pt) electrode, a gold (Au) electrode, or an aluminum electrode (Al). Preferably, the metal electrode 176 may comprise a thin layer of metal 178 which may be deposited onto a substrate, such as a further layer.

[0274] Further, the photodiode 134 has at least one photoactive layer 180 which comprises at least one electron donor material, preferably an organic polymer, and at least one electron acceptor material, preferably a fullerene-based electron acceptor material. In his particularly preferred example, the photoactive layer 180 comprises a blend of poly(3-hexylthiophene-2,5-diyl) (P3HT) as the organic polymer which may constitute the electron donor material and of [6,6]-phenyl-C61-butyric acid methyl ester (PC60BM) which may be employed as the fullerene-based electron acceptor material, wherein the blend of P3HT and PC60BM exhibits a ratio of 1:1. However, other kinds of electron donor materials and electron acceptor materials, in particular the materials as mentioned elsewhere in this application, as well as other ratios between two or more constituents of the blend may be used, mainly depending on the purposes of the optical detector 110.

[0275] According to the present invention, the photoactive layer 180 is embedded between the first electrode 166 and the second electrode 174. However, in this preferred embodiment, the photoactive layer may be embedded between a charge-carrier blocking layer 182 and a charge-carrier transporting layer 184 in a manner that the charge-carrier blocking layer 182 may further adjoin the first electrode 166 while the charge-carrier transporting layer 184 may additionally adjoin the second electrode 174. Alternatively, two different kinds of charge-carrier blocking layers 182 may be present in order to embed the photoactive layer 180. Herein, a first charge-carrier blocking layer may be a hole blocking layer while a second charge-carrier blocking layer may be an electron blocking layer. Herein, the electron blocking layer may be capable of achieving a similar effect as a hole transporting layer when embedding the photoactive layer. Again, in order to allow the incident light beam 132 reaching the photoactive layer 180, the charge-carrier blocking layer 182 may, preferably, be an optically transparent layer, such that the light beam 132, which impinges on the photodiode 134, may follow a beam path 186 within the photodiode through the optically transparent substrate 170, the optically transparent first electrode 166, and the optically transparent charge-carrier blocking layer 182 until it may arrive at the photoactive layer 180 as desired. However, other arrangements of the mentioned constituents within the photodiode 134, which may still allow the incident light beam 132 to at least partially reach the photoactive layer 180, may also be feasible.

[0276] In the preferred embodiment depicted in FIG. 2, the charge-carrier blocking layer may be a hole blocking layer which comprises a hole blocking material. Preferably, the hole blocking material may be selected to comprise polyethylenimine ethoxylate (PEIE) or a transition metal oxide, in particular ZnO, or a mixture thereof. However, other kinds of hole blocking materials, in particular the materials as mentioned elsewhere in this application, may be employed for this purpose. Herein, the thickness of the hole blocking layer may, preferably, be in a range to allow a significant short-cut current through the hole blocking layer under illumination of the photodiode 134, in particular in the range from 1 nm to 100 nm.

[0277] Further, the charge-carrier transporting layer may be a hole transporting layer which comprises a hole transporting material. Preferably, the hole transporting layer may be layer of poly-3,4-ethylenedioxythiophene (PEDOT), preferably, wherein the PEDOT may be electrically doped with at least one counter ion in particular, wherein the PEDOT may be doped with sodium polystyrene sulfonate (PEDOT:PSS). However, also here other kinds of hole transporting materials, in particular the materials as mentioned elsewhere in this application, may be used for this purpose.

[0278] A particular advantage of the setup of the photodiode 134 as schematically depicted in FIG. 2 may be attributed to an observation that one or more, preferably all, of the photoactive layer 180, the charge-carrier blocking layer 182, and the charge-carrier transporting layer 184 may be provided by using a deposition method, preferably by a coating method, more preferred by a spin-coating method or slot-coating method. Further, one or more of the electrodes 166, 174 within the photodiode 134 may be produced by depositing the respective electrode material onto a corresponding substrate by using a suitable deposition method, such as a coating or evaporation method. Consequently and in contrast to a dye-sensitized solar cell (DSC), preferably a solid-state dye-sensitized solar cell (ssDSC), an application of deposition methods does not require one or more annealing steps. By using an appropriate organic polymer, the maximum temperature as required for this kind of production methods may be selected to be below 140 C., below 120 C., below 100 C., or less, depending on the choice of the organic polymer in the photoactive layer 180. In addition, the application of the deposition methods allows a faster and energy-saving production of the photodiodes 134 since, generally, the deposition methods require less time and energy compared to time- and energy-consuming annealing processes.

[0279] FIG. 3 shows an experimental diagram which presents the steady-state current density j vs. voltage V characteristic of the optical detector 110 according to the present invention under illumination by an incident light beam 132. Herein, a first curve 188 relates to a first embodiment in which the photodiode 134 comprises PEIE as the hole blocking material 182 while a second curve 190 relates to a second embodiment in which the photodiode 134 comprises a mixture of ZnO and PEIE as the hole blocking material 182. However, in both cases, the photodiode 134 comprises ITO on the glass substrate 172 as the first electrode 166, the blend of P3HT and PC60BM as the photoactive layer 180, PEDOT as the hole transporting layer 184, and a silver layer as the second electrode 174. Alternatively, instead of using the hole transporting layer 184 an electron blocking layer, such as a molybdenum oxide or a nickel oxide, may be used. From FIG. 3 it may be derived that a photocurrent which is generated and extracted in the fourth quadrant as shown in FIG. 3, i.e. the quadrant where both the voltage and the steady-state current density exceed a value of zero, is known to be characteristic for a solar cell.

[0280] Surprisingly, as depicted in FIGS. 4A and 4B, the FiP effect may be observable in the optical detector 110 according to the present invention. In these experimental diagrams, an alternating current (ac) photocurrent I vs. a distance d of the longitudinal optical sensor 114 from the object 112 (FIG. 4A) and the ac photocurrent I vs. the frequency f of the modulated illumination source 142 for different focus conditions (FIG. 4B) are respectively shown.

[0281] As can be derived from FIG. 4A, both a first curve 192 and a second curve 194 clearly exhibit a positive FiP effect. Herein, the first curve 192 relates to the first embodiment as described in relationship to FIG. 3 in which the photodiode 134 comprises PEIE as the hole blocking material 182 while the second curve 194, again, relates to the second embodiment related to FIG. 3 in which the photodiode 134 comprises a mixture of ZnO and PEIE as the hole blocking material 182. Consequently, the ac photocurrent at short circuit conditions shows a characteristic maximum when a condition that the incident light beam 132 is focused onto the sensor region 130 of the longitudinal optical sensor 114 is fulfilled. In this particular example, the condition is fulfilled around a distance of approximately 24 mm between the longitudinal optical sensor 114 and the object 112 in the direction of view 126. For recording both the first curve 192 and the second curve 194 in FIG. 4A, the illumination source 136 has been modulated with the frequency of 375 Hz. As the modulated illumination source 142 a light-emitting diode 140 providing green light, i.e. a wavelength of the light beam 132 of 530 nm, has been employed.

[0282] In a further embodiment (not depicted here), other kinds of electron donor materials may also be suitable, in particular polymers being sensitive in the infrared spectral range, especially in the NIR range above 1000 nm, preferably diketopyrrolopyrrol polymers, in particular, the polymers as described in EP 2 818 493 A1, more preferably the polymers denoted as P-1 to P-10 therein; benzodithiophene polymers as disclosed in WO 2014/086722 A1, especially diketo-pyrrolopyrrol polymers comprising benzodithiophene units; dithienobenzofuran polymers according to US 2015/132887 A1, especially dithienobenzofuran polymers comprising diketo-pyrrolopyrrol units; phenantro[9, 10-B]furan polymers as described in US 2015/0111337 A1, especially phenantro [9, 10-B] furan polymers which comprise diketopyrrolopyrrol units; and polymer compositions comprising diketopyrrolopyrrol oligomers, in particular, in an oligomer-polymer ratio of 1:10 or 1:100, such as disclosed in US 2014/0217329 A1. As could be verified experimentally, the photodiodes 134 comprising these kinds of polymers in the photoactive layer 180, exhibit the desired negative FiP effect in the NIR range, particularly above 1000 nm.

[0283] As indicated above, FIG. 4B shows the ac photocurrent vs. the frequency of the modulated illumination source 142 at short-circuit conditions for an in-focus condition 196 and an out-of-focus condition 198, respectively. For both curves, the first embodiment as described in relationship to FIG. 3 in which the photodiode 134 comprises PEIE as the hole blocking material 182 has been used. As can be derived from FIG. 4B, a ratio between both curves at a selected frequency indicates that the optical detector according to the present invention which comprises the longitudinal optical sensor 114 having the photoactive layer 180 comprising the blend of the organic polymer and the fullerene-based electron acceptor material is suitable for being used in a distance sensor as well as, by further employing one or more of the transversal optical sensors 160, in a 3-dimensional sensor which are based on the FiP technology, in particular, known from WO 2012/110924 A1 and WO 2014/097181 A1.

[0284] As an example, FIG. 5 shows an exemplary embodiment of a detector system 200, comprising at least one optical detector 110, such as the optical detector 110 as disclosed in one or more of the embodiments shown in FIGS. 1 to 4. 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. 5 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. 5 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.

[0285] With regard to the optical detector 110 and to the detector system 200, 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. 5. The evaluation device may be connected to each of the at least two longitudinal optical sensors, in particular, by the signal leads 154. As described above, a use of two or, preferably, three longitudinal optical sensors 114 may support the evaluation of the longitudinal sensor signals without any remaining ambiguity. The evaluation device 150 may further be connected to the at least one optional transversal optical sensor 160, in particular, by the signal leads 154. By way of example, the signal leads 154 may be provided and/or one or more interfaces, which may be wireless interfaces and/or wire-bound interfaces. Further, the signal leads 154 may comprise one or more drivers and/or one or more measurement devices for generating sensor signals and/or for modifying sensor signals. Further, again, 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.

[0286] Further, the evaluation device 150 may fully or partially be integrated into the optical sensors and/or into other components of the optical detector 110. The evaluation device 150 may also be enclosed into the housing 118 and/or into a separate housing. The evaluation device 150 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 longitudinal evaluation unit 152 (denoted by z) and a transversal evaluation unit 162 (denoted by x y). By combining results derived by these evolution units, a position information 164, preferably a three-dimensional position information, may be generated (denoted by x y z).

[0287] Further, the optical detector 110 and/or to the detector system 200 may comprise an imaging device 210 which may be configured in various ways. Thus, as depicted in FIG. 5, the imaging device 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 signal leads 154 to the evaluation device 150 of the detector 110. Alternatively, the imaging device 210 may be separately located outside the detector housing 118. The imaging device 210 may be fully or partially transparent or intransparent. The imaging device 210 may be or may comprise an organic imaging device or an inorganic imaging device. Preferably, the imaging device 210 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.

[0288] In the exemplary embodiment as shown in FIG. 5, 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 212, the position and/or orientation of which may be manipulated by a user 214. Thus, generally, in the embodiment shown in FIG. 5 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 212, specifically, wherein the at least one control element 212 has one or more beacon devices 216, wherein a position and/or orientation of the control element 212 preferably may be manipulated by user 214. 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 214 may be considered as the object 112, the position of which shall be detected. As an example, the user 214 may carry one or more of the beacon devices 216 attached directly or indirectly to his or her body.

[0289] The optical detector 110 may be adapted to determine at least one item on a longitudinal position of one or more of the beacon devices 216 and, optionally, at least one item of information regarding a transversal position thereof, and/or at least one other item of information regarding the longitudinal position of the object 112 and, optionally, at least one item of information regarding a transversal position of the object 112. 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 216 which might comprise different colors. The opening in the housing, which, preferably, may be located concentrically with regard to the optical axis of the detector 110, may preferably define a direction of a view of the optical detector 110.

[0290] 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 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 218. In the embodiments schematically depicted in FIG. 5, the machine 218 may be or may comprise at least one computer and/or a computer system comprising the data processing device 158. Other embodiments are feasible. The evaluation device 150 may be a computer 156 and/or may comprise a computer 156 and/or may fully or partially be embodied as a separate data processing device 158 and/or may fully or partially be integrated into the machine 218, particularly the computer. The same holds true for a track controller 220 of the tracking system 208, which may fully or partially form a part of the evaluation device 150 and/or the machine 218.

[0291] Similarly, as outlined above, the human-machine interface 204 may form part of the entertainment device 206. Thus, by means of the user 214 functioning as the object 112 and/or by means of the user 214 handling the object 112 and/or the control element 212 functioning as the object 112, the user 214 may input at least one item of information, such as at least one control command, into the machine 218, particularly the separate data processing device 158, thereby varying the entertainment function, such as controlling the course of a computer game.

LIST OF REFERENCE NUMBERS

[0292] 110 detector [0293] 112 object [0294] 114 longitudinal optical sensor [0295] 116 optical axis [0296] 118 housing [0297] 120 transfer device [0298] 122 refractive lens [0299] 124 opening [0300] 126 direction of view [0301] 128 coordinate system [0302] 130 sensor region [0303] 132 light beam [0304] 134 photodiode [0305] 136 illumination source [0306] 138 artificial illumination source [0307] 140 light-emitting diode [0308] 142 modulated illumination source [0309] 144 modulation device [0310] 146 first beam path [0311] 148 second beam path [0312] 150 evaluation device [0313] 152 longitudinal evaluation unit [0314] 154 signal leads [0315] 156 computer [0316] 158 data processing device [0317] 160 transversal optical sensor [0318] 162 transversal evaluation unit [0319] 164 position information [0320] 166 first electrode [0321] 168 transparent conductive oxide [0322] 170 optically transparent substrate [0323] 172 glass substrate [0324] 174 second electrode [0325] 176 metal electrode [0326] 178 thin metal layer [0327] 180 photoactive layer [0328] 182 charge-carrier blocking layer [0329] 184 charge-carrier transporting layer [0330] 186 beam path within photodiode [0331] 188 first curve [0332] 190 second curve [0333] 192 first curve [0334] 194 second curve [0335] 196 in-focus condition [0336] 198 out-of-focus condition [0337] 200 detector system [0338] 202 camera [0339] 204 human-machine interface [0340] 206 entertainment device [0341] 208 tracking system [0342] 210 imaging device [0343] 212 control element [0344] 214 user [0345] 216 beacon device [0346] 218 machine [0347] 220 track controller