WO2013139434A1 - Procédé de lecture ultrarapide de photodétecteurs - Google Patents
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- WO2013139434A1 WO2013139434A1 PCT/EP2013/000638 EP2013000638W WO2013139434A1 WO 2013139434 A1 WO2013139434 A1 WO 2013139434A1 EP 2013000638 W EP2013000638 W EP 2013000638W WO 2013139434 A1 WO2013139434 A1 WO 2013139434A1
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- photodetectors
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- train signal
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- 238000000034 method Methods 0.000 title claims abstract description 43
- 230000003287 optical effect Effects 0.000 claims abstract description 79
- 230000003111 delayed effect Effects 0.000 claims abstract description 43
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- 230000003595 spectral effect Effects 0.000 claims description 22
- 230000002123 temporal effect Effects 0.000 claims description 17
- 238000001228 spectrum Methods 0.000 claims description 11
- 230000035484 reaction time Effects 0.000 claims description 5
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 4
- 229910052710 silicon Inorganic materials 0.000 claims description 4
- 239000010703 silicon Substances 0.000 claims description 4
- 230000005855 radiation Effects 0.000 description 12
- 238000012545 processing Methods 0.000 description 11
- 238000009826 distribution Methods 0.000 description 8
- 238000005070 sampling Methods 0.000 description 8
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- 206010034972 Photosensitivity reaction Diseases 0.000 description 1
- XBJJRSFLZVLCSE-UHFFFAOYSA-N barium(2+);diborate Chemical compound [Ba+2].[Ba+2].[Ba+2].[O-]B([O-])[O-].[O-]B([O-])[O-] XBJJRSFLZVLCSE-UHFFFAOYSA-N 0.000 description 1
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Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J3/00—Spectrometry; Spectrophotometry; Monochromators; Measuring colours
- G01J3/28—Investigating the spectrum
- G01J3/2803—Investigating the spectrum using photoelectric array detector
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J1/00—Photometry, e.g. photographic exposure meter
- G01J1/42—Photometry, e.g. photographic exposure meter using electric radiation detectors
- G01J1/4228—Photometry, e.g. photographic exposure meter using electric radiation detectors arrangements with two or more detectors, e.g. for sensitivity compensation
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J1/00—Photometry, e.g. photographic exposure meter
- G01J1/42—Photometry, e.g. photographic exposure meter using electric radiation detectors
- G01J1/44—Electric circuits
Definitions
- the present invention is in the field of photosensitivity. More particularly, it relates to a method and apparatus for ultrafast reading of at least two spaced-apart photodetectors and a spectrometer utilizing such an apparatus and method.
- TDI-CCD cameras Time Delay Integration
- Another application in which a plurality of photodetectors is read out, forms the spectroscopic examination of substances.
- the radiation to be analyzed is spatially separated so that different spectral radiation components run on different optical paths after separation.
- a diffractive optical element can be used.
- the spatial intensity distribution thus provided can then be detected by optical detectors which are spaced from each other.
- the signal generated by the detectors is further processed, for which purpose the detectors are read out.
- said spectrometric applications are used to observe time-varying processes.
- a prerequisite for this is the possibility of a time-resolved execution of the optical detection measurements at the spatially spaced apart detectors. If the processes to be investigated run on very short time scales, it is also essential that the signals are generated quickly and sensitively on the one hand, and that they are further processed correspondingly quickly after generation, on the other hand.
- Time-resolved analysis is the use of pulsed radiation whose spectral information - after interaction with the sample to be examined - is determined.
- Time-sequential optical pulses characterize the sample at different times and may be captured by a photodetector as "snapshots.”
- individual spectral slices may be received in time-resolved fashion.
- CCD sensors These form the optical detector and the readout a common, integrated device.
- clock signals in the MHz range can be used.
- the sampling rate essentially results from the product of the inverse of the number of pixels and the clock signal frequency. Dead-time clock cycles in which dark pixels are output are not taken into account.
- the sampling rates for very fast line detectors are usually in the range of a few 10 kHz, ie they correspond to a time resolution of about 100 ⁇ 8.
- the use of actively switched components for signal processing thereby results in a relatively high noise level. These components have a complex circuit with its own timing, which limits the sampling rate.
- CCD imaging systems have a mechanical shutter or are modulatedly illuminated.
- the modulation can be generated with an electro-optical modulator, with an acousto-optical modulator or with a rotating perforated disc. In this case, it is necessary to synchronize the sampling rate with the modulator.
- the mechanical shutter or the modulating components limit the technically achievable sampling rate.
- spatial intensity distributions can also be measured by mechanically adjustable detection mechanisms.
- a photodiode used for detection can be moved by means of a displacement table, as described in the patent application US 4,124,297.
- Another possibility describes the patent application US 4,732,476, in which the scanning of a spectral intensity distribution by rotating an optical grating takes place.
- the recording duration of a spectrum is in the range of milliseconds to minutes. For a temporal analysis of spectra in the microsecond range, these recording methods are therefore unsuitable.
- Another method uses a spatial arrangement of photodiodes, for example a photodiode array, and uses for reading each photodiode each have their own preamplifier and a separate analog-to-digital converter.
- the digital signals thus generated contain the optical information of the detected spectrum at the location of the photodiode at the time of detection.
- Very high sampling rates can be achieved with this method.
- this method is very costly, especially when additionally using lock-in amplifiers to process the photodiode signals.
- the previously known methods for time-resolved reading of a detector device for recording a spatial intensity distribution have the disadvantage that the time resolution is either limited to a range of about 100 ⁇ 3 or can only be achieved at considerable expense.
- the present invention has for its object to provide a method that allows a large number of spatially spaced photodetectors, which are illuminated by optical pulses with repetition rates up to the MHz range, inexpensive and low noise read. Another object is to provide a device that uses this method.
- Modern ultrashort pulse lasers emit optical pulses with typical pulse durations in the nano-, pico- or femtosecond range with repetition rates in the MHz range.
- each photodetector When a plurality N of spaced-apart photodetectors are illuminated with optical pulses, each photodetector generates an output electrical pulse approximately simultaneously in response to each of these optical pulses.
- the repetition rate of the electrical output pulses generated by a photodetector corresponds to the repetition rate of the optical pulses with which the photodetector is illuminated.
- a plurality N of pulsed electrical signals are generated upon detection of a pulsed spatial intensity distribution. So far, it is not possible to read these signals as quickly as they are provided in a cost effective manner.
- the present invention solves this problem by a method of reading out a plurality N of photodetectors, where N is an integer> 2 and the photodetectors are spaced apart and illuminated simultaneously by an optical pulse so that each of the N photodetectors respond in response to the photodetectors optical pulse generates at least approximately simultaneously an electrical output pulse.
- the information contained in the optical pulse can be detected location-dependent by the plurality N of photodetectors.
- Each photodetector thus detects optical information, for example the intensity of a specific radiation component, at a specific spatial position.
- the optical pulse may include, for example, visible, Near Infrared (NIR), infrared (IR), ultraviolet (UV), and / or other radiation regions.
- NIR Near Infrared
- IR infrared
- UV ultraviolet
- the present invention is used in the visible and NIR range and with photon energies of preferably ⁇ 100 eV, preferably ⁇ 10 eV and most preferably ⁇ 3 eV.
- the information contained in the optical pulse is represented by the temporal and spatial spectral intensity distribution.
- the spatial spectral information can be detected either without or with prior spectral separation. If the spectral sensitivity ranges of the photodetectors are selected differently from each other and narrow with respect to the spectrum of the optical pulse, only a corresponding spectral section of the spectrum of the optical pulse is detected at the location of each photodetector. In this case, a preliminary spectral separation is not necessary.
- the spectral components of the optical pulse are spatially separated before detection, they can be identical spaced apart photodetectors that are sensitive in the entire spectrum of the optical pulse can be detected.
- the spectral separation can be made by means of an optical grating or a refractive optical element.
- the N photodetectors generate a plurality of N output electrical pulses in response to the incident optical pulse. Each of these electrical output pulses contains the information of the optical pulse at the location of the photodetector. Since the optical pulse impinges on the plurality N of photodetectors approximately simultaneously, the plurality of output electrical pulses are also generated approximately simultaneously in response to this optical pulse. Delays in the propagation of an optical pulse propagating at the speed of light or else different reaction times of the photodetectors can lead to different times of impingement of the optical pulse on the photodetectors or at different production instants of the electrical output pulses.
- the temporal relationship between the generation times is referred to as "approximately simultaneous.”
- the N delay times Ty , i are different from each other in pairs, so that the delayed output pulses are offset in pairs in time with respect to each other It is also possible that one of the delay times is zero, ie all output pulses except one are delayed in time.
- these N delayed output pulses are combined to form a pulse train in a pulse train signal.
- N individual signals are combined into a single signal, the pulse train signal.
- Each electrical output pulse is represented in the pulse train signal in the form of a contribution from a particular photodetector. Due to the different delay times ⁇ , ⁇ , successive contributions of a pulse train in the pulse train signal have a time interval from each other which corresponds to the difference between the associated delay times ⁇ , ⁇ . Furthermore, the contributions in the pulse train signal occupy a certain temporal section, which is determined by the corresponding delay time ⁇ , ⁇ and a specific offset value.
- the pulse train signal is read out using a readout circuit.
- the read-out takes place in such a way that each photodetector is assigned a specific time segment of the pulse train signal belonging to a specific delay time Ty, i.
- the abovementioned offset value can be determined by means of a trigger signal, so that each contribution can be assigned to the corresponding detector and the corresponding optical pulse.
- the trigger signal can be generated, for example, from the output signal of an additional photodetector or from a signal which has been diverted to one of the N instantaneous or delayed electrical output pulses. Alternatively, the trigger signal can also be generated by the control of the pulsed laser.
- substantially non-overlapping in time in this context means that successive contributions in the pulse train signal are so far apart in time that the read-out circuit can still distinguish them from one another and thus assign the information contained to the respective photodetector
- the pulse width usually corresponds to the half width, ie the full width of the contribution at half the amount of the contribution
- the critical time interval ie the distance at which successive contributions of the same pulse train do not substantially overlap in time, can be determined by the further processing of the pulse train signal to be dependent.
- the method according to the invention thus converts information from a spatial intensity distribution into a single pulse train signal.
- the spatial position of a photodetector is translated into the position of a temporal section in the pulse train signal.
- the spectral information contained in a contribution is assigned to the corresponding spatial position.
- the read speed corresponds to the speed at which the information is provided.
- Delaying and merging can take place, for example, temporally and spatially separated from one another.
- the N output pulses are delayed by means of the delay means first individually and in pairs separately from each other to the N delayed output pulses. Subsequently, these N delayed output pulses can then be merged.
- the first process step of deceleration and the second process step of merging are not necessarily performed one after another but may also be combined or combined with each other.
- a certain number of delay sections are connected in series and different photodetectors are each connected to different points of this series connection.
- different electrical output pulses each enter the series circuit at different points and each undergo a different number of delay sections.
- the Nth electrical output pulse is delayed by one time (TV , N-TV, NI) and then combined with the (Nl) th instantaneous electrical output pulse to form a two-contribution signal.
- This two-contribution signal is delayed by the time ( ⁇ , ⁇ - ⁇ - ⁇ , ⁇ -2) and with the (N-2) th instantaneous electrical output pulse a signal with three contributions. These steps are repeated until finally a signal with Nl amounts is delayed by the time (T v> 2 - T v, i) and then merged with the first instantaneous electrical output pulse to the pulse train signal.
- Delaying is preferably done using passive delay means, "passive" meaning that no active switching, such as using a clock signal, is necessary for deceleration, for example a passive delay may be caused by the propagation delay in a cable
- passive delay means allows a readout in quasi-real time, ie the signal readout is carried out at practically the same speed as the signal supply and is only delayed by transit time differences
- a limitation of the time resolution by active delay, such as due to a buffering or due to a clock signal frequency, is not available.
- the N delay times Ty , i have a value which corresponds to a multiple of a predetermined time interval At.
- the time interval between two consecutive contributions of the same pulse train is constant and corresponds to the value of the predetermined time interval At.
- a pulsed laser source is used to scan the sample to be examined and the photodetectors are illuminated with this plurality of optical pulses interacting with the sample, a pulse train signal is generated containing a pulse train of N contributions for each optical pulse.
- the contributions of the same pulse train take in the pulse train signal a time range ⁇ , the magnitude of which depends on the choice of the delay times Ty , i.
- the delay times are chosen so that the temporal range ⁇ is less than 1 / f rep .
- the critical distance should be as small as possible and thus the pulse width of the contributions should be as narrow as possible.
- the pulse width of the contributions is in the range of the reaction time T R of the photodetector and is limited by this.
- the response time T R of a photodetector is usually defined by the time it takes for a signal to increase from 10% to 90% of the maximum value.
- the reaction time T R of a photodetector is approximately the limit frequency f c by T R ⁇ 0.35 / fc, wherein the cutoff frequency f c is the frequency at which the signal value has dropped to around 50% of the maximum value.
- fast photodetectors are preferably used which have reaction times T R which are preferably ⁇ 50 ns, preferably ⁇ 5 ns, particularly preferably ⁇ 0.1 ns.
- the photodetectors used have cut-off frequencies f c which are preferably> 0.007 GHz, preferably> 0.07 GHz, particularly preferably> 3.5 GHz.
- the delay times are chosen so that the predetermined time interval ⁇ t can preferably be chosen to be less than 100 ns, preferably less than 10 ns and particularly preferably less than 100 ps.
- the pulse train signal is amplified by means of a preamplifier, before the assignment of the temporal sections to the respective photodetector takes place.
- the pulse train signal is digitized by means of an analog-to-digital converter before the assignment of the time segments to the respective photodetector takes place. Note that only a single preamplifier and a single analog-to-digital converter is needed to read the N photodetector signals for further processing. This shows a particular advantage of generating the analogue Pulse train signal from the plurality of delayed individual signals.
- the method according to the invention is used in a spectrometer for determining the spectrum of an optical pulse.
- the spectral components of the optical pulse are spatially separated. This separation is made, for example, as previously mentioned, by means of a refractive optical element or by means of an optical grating.
- the spectrometer comprises a plurality of N photodetectors which are spaced apart and illuminated with different spectral components of the optical pulse. The readout of the photodetectors is carried out as described above.
- the contributions in the pulse train signal contain the spectral information of the optical pulse at the location of the photodetector.
- This information can be represented, for example, by the amplitude of the respective contribution, the width of the respective contribution, the integrated amplitude of the respective contribution or by another quantity of the respective contribution of the pulse train signal which is indicative of the intensity of the light received at the associated photodetector. By determining this quantity, the detected radiation intensity at the location of the photodetector is determined.
- the invention also includes a device for reading out the plurality N of photodetectors using this method.
- the device according to the invention comprises the following elements:
- the delay means can be realized, for example, by cables of different lengths, so that the electrical output pulses generated by the photodetectors travel different distances through the cables. Due to different lengths of maturity, the electrical output pulses are delayed by different delay times Tv , i and thus offset in time.
- Another possibility is to use commercially available passive delay elements that have a rise time of no more than 1 ns and delay times in the range of about 100 ps to nanoseconds. If necessary, several of these elements can be connected in series to achieve higher delay times.
- a further embodiment provides a propagation delay directly in the semiconductor material of the photodetector. Due to a relatively low propagation speed of the electrical output pulses in semiconductors, therefore, only a relatively small distance is required.
- the means for combining the delayed output pulses may be, for example, commercially available combination elements. These include, for example, N input cables which are connected together at their outputs and terminate in a single output cable.
- the means for reading comprise an analog-to-digital converter.
- an analog pulse train signal can be converted into a digital signal and then further processed with a suitable data processing system.
- the means for reading comprises a preamplifier. With this, the contributions of the pulse train signal can be amplified, whereby the further processing is simplified.
- the device comprises a plurality N of photodetectors for detecting the optical pulse and for generating the electrical output pulses.
- the device For use with visible light, for example, silicon photodiodes or photodiode cells can be used.
- An advantageous development of the invention relates to a spectrometer for determining the spectrum of an optical pulse using a plurality N of photodetectors, where N is an integer> 2 and the photodetectors are spaced from each other and arranged so that they each light of an associated spectral range of the optical pulse receive.
- the spectrometer includes the aforementioned delay means, means for merging and means for reading.
- the spectrometer comprises means for determining a size of the pulse train signal which is indicative of the intensity of the light received at the associated photodetector. The determined variable can be assigned to the spatial position of the corresponding photodetector and thus the spectrum of the optical pulse can be determined.
- Figure 1 is a schematic representation of a preferred embodiment of
- FIG. 2 shows a schematic representation of a pulse train signal
- Figure 3 is a schematic representation of an alternative embodiment of the
- FIG. 4 shows a schematic representation of the structure for measuring a pulse train signal
- FIG. 5 shows a measured pulse train signal using two photodetectors.
- FIG. 1 shows a schematic representation of a preferred embodiment of the readout device 8 according to the invention, with which a pulse train signal 10, as shown in Figure 2, can be generated. More specifically, FIG. 1 shows on the left side an optical pulse 12 and, to the right, a plurality N of photodetectors 14. The photodetectors 14 are connected to delay means 18. These are followed by means 22 for combining delayed output pulses 20, to which an analog-to-digital converter 24 is connected, followed by a data processing system 26. In each photodetector 14, an electrical output pulse 16 is generated in response to the optical pulse 12, which is shown schematically in Figure 1. In the direction of passage behind the delay means 18 also delayed output pulses 20 and behind the means 22 for merging a pulse train signal 10 are shown schematically.
- the function of the read-out device 8 will be described below.
- the optical pulse 12 is represented by a plurality of arrows. In this case, an arrow corresponds to a spatial section of the optical pulse 12, which impinges on a specific photodetector of the plurality N of photodetectors 14.
- each of the plurality N of photodetectors 14 generates an electrical output pulse 16 approximately simultaneously.
- Output pulse 20 is generated.
- the output pulse 16 of the first photodetector 14 would be a "delayed" output pulse delayed by a delay time of zero to standardize the description Output pulses 20 of the (i + l) -th and (i-l) -th photodetector 14 temporally offset by the predetermined time interval At.
- the analog pulse train signal 10 is digitized by means of an analog-to-digital converter 24 and the thus digitized signal is forwarded to a data processing system 26.
- FIG. 2 shows the time profile of the signal strength of a pulse train signal 10, as generated by the read-out device 8 shown in FIG.
- the illustrated pulse train signal 10 includes three pulse trains 48, each containing a number N of contributions 28. The totality of the contributions 28 of the same pulse train 48 increases in the pulse train signal
- the contributions 28 each have a pulse width 44 which corresponds to the full width of a contribution 28 at half the contribution level.
- the time interval ⁇ t is sufficiently greater than the pulse width 44, so that the pulses of the same pulse train 48 do not overlap in time, or at least substantially do not overlap.
- substantially not overlapping in time means that successive contributions 28 in the pulse train signal 10 are so far apart in time that they can still be separated from one another during further processing of the pulse train signal 10, so that the information contained in each contribution 28 corresponds to the corresponding one
- the pulse spacing 32 is between the contributions 28 of the same photodetector
- the pulse train spacing 32 corresponds to the spacing of successive optical pulses 12.
- FIG. 3 shows a schematic representation of an alternative embodiment.
- an optical pulse 12 impinges on a plurality N of photodetectors 14.
- the proportions of the optical pulse 12 in FIG. 3 are occupied from bottom to top with the numbers "1" to "N".
- the N photodetectors 14 are connected via N connections - represented by lines - to means 34 for merging and delaying.
- the means 34 for merging and delaying include Nl individual delay sections 35, of which only four are drawn.
- the Nl delay sections 35 are connected in series, so that the output (bottom) of a delay section 35 is connected to the input (top) of the subsequent delay section 35, and from bottom to top - in the opposite direction of the signals through the series connection - numbered from "2" to "N".
- the i-th of the N photodetectors 14 is connected to the input of the i-th delay section 35.
- the first of the N photodetectors 14 is connected to the output of the second delay section 35 and to an analog-to-digital converter 24.
- a data processing system 26 is shown, which is connected downstream of the analog-to-digital converter 24.
- FIG. 4 is a schematic representation of an experimental setup intended to demonstrate the operability of the present invention.
- a laser system 36 which provides pulsed radiation with a wavelength of 1.55 ⁇ , with a repetition rate of 4 MHz and with a pulse duration of 100 femtoseconds.
- Element 38 is shown for doubling the frequency of the emitted laser radiation.
- a plurality of photodetectors 14 for detecting an optical pulse and for generating electrical output signals.
- a readout circuit 40 is connected, which in turn is connected to an oscilloscope 42.
- a sample to be examined with which the optical pulse 12 can interact is not shown in FIG. 4. Since only the functionality of the present invention is to be shown by the illustrated construction of Fig. 4, the pulsed spatial laser radiation is direct, i. without prior reflection from a sample to be examined or prior transmission through a sample to be examined, directed to the photodetectors 14.
- the radiation emitted by the laser system 36 is first passed through the frequency doubling element 38, which consists, for example, of a beta barium borate crystal, to halve the central wavelength of the optical pulses 12 to a wavelength of approximately 775 nm. This is necessary in the frequency doubling element 38, which consists, for example, of a beta barium borate crystal, to halve the central wavelength of the optical pulses 12 to a wavelength of approximately 775 nm. This is necessary in the
- the individual silicon photodetectors 14 are now illuminated with optical pulses 12 having a wavelength of about 775 nm at a repetition rate of 4 MHz and in response generate output electrical pulses 16, which are passed to the readout circuit 40.
- the readout circuit 40 includes the
- FIG. 5 shows a pulse train signal 10 represented by the oscilloscope 42 of FIG. 4.
- the time segment shown here shows seven pulse trains 48 each having two contributions 28.
- the pulse train spacing 32 between the contributions 28 of the same photodetector 14 from successive optical pulses 12 is about 250 ns.
- the pulse width 44 of the contributions 28 is about 15 ns.
- FIG. 5 shows reflections 46 whose signal strength amounts to approximately 20% of the signal strength of the posts 28. These reflections can arise, for example, at connection points of the cables.
- the experimental setup of Figure 4 and the pulse train signal 10 of Figure 5 demonstrate the operability of the present invention.
- the number of illuminated photodetectors 14, which in the experimental setup of FIG. 4 is only 2 can already be significantly increased without any other modifications. without the contributions 28 in the pulse train signal 10 substantially overlapping in time.
- the number of photodetectors 14 could already be increased to 10 or more in the described construction.
- the number of detectors can even be increased considerably.
- the pulse train signal 10 can optionally be optimized with respect to the required temporal and spatial resolution.
- the lower the requirement for the temporal resolution the lower the laser frequency can be selected. This has resulted in a larger pulse spacing 32 so that a pulse train 48 may comprise more temporally substantially non-overlapping contributions 28.
- the number of photodetectors 14 and thus the spatial resolution can be increased.
- the temporal resolution can also be increased by reducing the spatial resolution.
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Abstract
L'invention concerne un procédé et un dispositif de lecture ultrarapide d'une pluralité N de photodétecteurs espacés les uns des autres et illuminés simultanément par une impulsion optique, de manière que chacun de N photodétecteurs produit au moins sensiblement simultanément une impulsion électrique de sortie en réponse à cette impulsion optique. Lesdites N impulsions de sortie sont retardées d'un temps de retard respectif par un moyen applicateur de retard. Les N impulsions de sortie retardées sont réunies pour former un signal à train d'impulsions, et le signal à train d'impulsions est lu au moyen d'un circuit de lecture.
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DE201210102521 DE102012102521A1 (de) | 2012-03-23 | 2012-03-23 | Verfahren zum ultraschnellen Auslesen von Fotosensoren |
DE102012102521.5 | 2012-03-23 |
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WO2013139434A1 true WO2013139434A1 (fr) | 2013-09-26 |
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Cited By (1)
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CN112904312A (zh) * | 2021-01-25 | 2021-06-04 | 深圳煜炜光学科技有限公司 | 一种激光雷达抗干扰的方法与装置 |
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JPS5858423A (ja) * | 1981-10-01 | 1983-04-07 | Toshiba Corp | 多波長分光光度計 |
US4465940A (en) * | 1982-04-15 | 1984-08-14 | The United States Of America As Represented By The Secretary Of The Air Force | Electro-optical target detection |
US4732476A (en) | 1985-07-26 | 1988-03-22 | Barspec Ltd. | Continuously rotating grating rapid-scan spectrophotometer |
JPH04177154A (ja) * | 1990-11-13 | 1992-06-24 | Toshiba Corp | 表面検査装置 |
US20110101208A1 (en) * | 2007-08-21 | 2011-05-05 | Nippon Telegraph And Telephone Corporation | Photocurrent monitoring circuit |
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US4678917A (en) * | 1985-02-19 | 1987-07-07 | The Perkin-Elmer Corporation | Instantaneous reading multichannel polychromatic spectrophotometer method and apparatus |
-
2012
- 2012-03-23 DE DE201210102521 patent/DE102012102521A1/de not_active Withdrawn
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2013
- 2013-03-05 WO PCT/EP2013/000638 patent/WO2013139434A1/fr active Application Filing
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US3486822A (en) | 1965-10-01 | 1969-12-30 | Lee B Harris | Sampling unit for continuous display of spectral analysis |
US4124297A (en) | 1977-07-25 | 1978-11-07 | The United States Of America As Represented By The Secretary Of The Navy | Ultrafast scanning spectrophotometer |
JPS5858423A (ja) * | 1981-10-01 | 1983-04-07 | Toshiba Corp | 多波長分光光度計 |
US4465940A (en) * | 1982-04-15 | 1984-08-14 | The United States Of America As Represented By The Secretary Of The Air Force | Electro-optical target detection |
US4732476A (en) | 1985-07-26 | 1988-03-22 | Barspec Ltd. | Continuously rotating grating rapid-scan spectrophotometer |
JPH04177154A (ja) * | 1990-11-13 | 1992-06-24 | Toshiba Corp | 表面検査装置 |
US20110101208A1 (en) * | 2007-08-21 | 2011-05-05 | Nippon Telegraph And Telephone Corporation | Photocurrent monitoring circuit |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN112904312A (zh) * | 2021-01-25 | 2021-06-04 | 深圳煜炜光学科技有限公司 | 一种激光雷达抗干扰的方法与装置 |
CN112904312B (zh) * | 2021-01-25 | 2024-01-30 | 深圳煜炜光学科技有限公司 | 一种激光雷达抗干扰的方法与装置 |
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DE102012102521A1 (de) | 2013-09-26 |
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