Electronic binoculars

Abstract

Electronic Binoculars The present invention relates to electronic binoculars (10) comprising: an optical flow capture assembly (12) from a scene, an optical flow display assembly (14) comprising: a microscreen (34) for displaying an image according to the captured optical flow, and at least one eyepiece (36) for viewing the image displayed by the microscreen (34), a proximity detection assembly (16) for a user relative to at least one eyepiece (36), and a control assembly (18) for the display of the microscreen (34) according to the optical flow captured by the capture assembly (12) and the detection performed by the detection assembly (16), such that the microscreen (34) is activated only when proximity is detected by the detection assembly (16). Figure for the abstract: 2

Description

Title of the invention: Electronic binoculars

[0001] The present invention relates to electronic binoculars.

[0002] More specifically, the invention relates to electronic binoculars equipped with a microscreen, particularly for use at night. Such binoculars include, for example, image-intensified night vision binoculars or thermal binoculars. The microscreen displays, within the range of wavelengths visible to the human eye, the image of the optical flow captured by the binoculars' video detector.

[0003] However, during night use, the light emitted by the microscreen is easily noticeable, especially when the user moves the binoculars closer to or further from their eyes and this light is reflected on their face.

[0004] Various solutions are known from the prior art for turning off the microscreen when the binoculars are not in use.

[0005] In particular, a first solution consists of turning off the microscreen by pressing a button on the binoculars. This solution is functional, but not automatic.

[0006] It is also known to detect the user's presence by means of an infrared (IR) transceiver on the binoculars. This allows for automatic control of the binoculars. However, this solution is not usable in a military environment because the IR emitter illuminates the user's face as much as, or even more than, the microscreen.

[0007] Another solution involves detecting the presence of a user by measuring a pressure difference between the inside and outside of the lens hood. However, this requires creating a pressure difference between the inside and outside of the lens hood, which impacts the battery life and stealth of the binoculars.

[0008] Yet another solution involves using a mechanical device to open diaphragms by pressing on the eyecups of the eyepieces. However, this requires constantly pressing the binoculars against the eye sockets. Furthermore, this solution does not offer the possibility of increasing battery life by turning off the microscreen.

[0009] Yet another solution involves detecting the presence of a user using a vibration and movement sensor. However, this is not compatible with observation from a tripod or observation from a height looking downwards (tower or helicopter looking down).

[0010] There is therefore a need for a means of automatically switching off the microscreen of electronic binoculars as soon as the user moves the binoculars away from their face, under all circumstances, particularly in a military context, and while being

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[0015] easy to use. For this purpose, the present description concerns electronic binoculars comprising: - a system for capturing an optical stream from a scene, - a system for reproducing the captured optical flow, comprising: • a microscreen designed to display an image based on the captured optical flow, and • at least one eyepiece for viewing the image displayed by the microscreen, - a proximity detection system for a user relative to at least one eyepiece, the detection system comprising: • a capacitive sensor positioned so that its capacitance fluctuates when a user approaches or moves away from it, said capacitance being the sum of a surrounding capacitance and a possible capacitance related to the proximity of the user, • a proximity detection block for a user relative to at least one eyepiece, based on the capacitive sensor's capacity and a detection threshold, the detection threshold being set according to the surrounding capacitance in the absence of detected proximity, and • a calibration block designed to update the detection threshold to compensate for variations in surrounding capacity, the calibration block being designed to perform the update only when no proximity is detected by the detection system, so that the detection threshold is fixed at its last value upon proximity detection, and - a control set for the display of the microscreen based on the optical flow captured by the capture set and the detection performed by the detection set so that the microscreen is activated only when a proximity is detected by the detection set. Depending on specific embodiments, electronic binoculars include one or more of the following features, taken individually or in all technically possible combinations: - each eyepiece is formed of a metallic body, the capacitive sensor being the metallic body of the or at least one of the eyepieces; - the detection block is designed to detect proximity based on the phase variations of a signal internal to the detection block and the detection threshold, the phase variations being a function of the capacitive sensor's capacity; - The detection unit includes: - an oscillator designed to generate a clock signal, called the internal signal, - a phase shifter, called a detection phase shifter, designed to shift the phase of the internal signal depending on the capacitive sensor's capacity, to obtain a detection signal, - a phase shifter, called a reference phase shifter, designed to phase shift the internal signal in an adjustable manner, to obtain a sampling signal, the reference phase shifter being set according to the detection threshold, - a sampler suitable for sampling the detection signal from the sampling signal to obtain an output signal, the output signal being suitable for taking two states such that: • when the phase of the detection signal is less than that of the sampling signal, the output signal is in a first state, indicating a lack of detected proximity, and • when the phase of the detection signal is greater than that of the sampling signal, the output signal is in a second state, indicating proximity detection;

[0016] -1'sampler is suitable for sampling the detection signal on both sampling signal edges;

[0017] - the detection block further comprises a dual time constant filter suitable for validating the output signal indicating proximity detection or not, only after obtaining a predetermined number of consecutive samples of the detection signal giving an output signal in the same state;

[0018] - the detection block includes a protection module between the capacitive sensor and the detection phase shifter, the protection module being designed to filter high-frequency radiation and / or to provide protection against electrostatic discharges;

[0019] - the detection threshold is formed by the sum of a moving average of the capacity surrounding in the absence of detection and a sensitivity gap;

[0020] - the sensitivity gap is adjustable by a user so as to adjust the distance to from which point the detection block detects proximity;

[0021] - the calibration block is suitable for updating the detection threshold at a frequency predetermined;

[0022] - electronic binoculars are light-intensifying binoculars or thermal binoculars.

[0023] Other features and advantages of the invention will become apparent from the following description of embodiments of the invention, given by way of example only and with reference to the drawings which are:

[0024] [Fig.1], [Fig.1], a schematic representation of an example of electric binoculars Ironics comprising a capture system, a playback system, a detection system, and a control system,

[0025] [Fig.2], [Fig.2], a schematic representation of an example of a mode of rea lisation of the electronic twins of the [Fig.1],

[0026] [Fig.3], [Fig.3], a schematic representation of another example of an embodiment of the electronic binoculars of [Fig.1],

[0027] [Fig.4], [Fig.4], a schematic representation of an example embodiment of the detection system of [Fig. 1], and

[0028] [Fig.5], [Fig.5], a schematic representation of an example of the detection threshold updated by the calibration block as a function of the detection or not of a proximity.

[0029] An example of electronic binoculars 10 is schematically illustrated in [Fig. 1]. More specific embodiments are illustrated in Figures 2 and 3.

[0030] Electronic binoculars 10 are, for example, image-intensifying binoculars or thermal binoculars. Electronic binoculars 10 include all types of binoculars, including monocular binoculars, binocular binoculars, binocular binoculars, and panoramic binoculars (4-way image intensifier).

[0031] As seen in [Fig.1], the binoculars 10 comprise a capture set 12, a rendering set 14, a detection set 16 and a control set 18. The capture set 12, the rendering set 14 and the detection set 16 are all three connected to the control set 18 to exchange information with this control set 18.

[0032] The capture assembly 12 is suitable for capturing an optical flow from a scene.

[0033] As illustrated by the examples in Figures 2 and 3, the capture assembly 12 comprises at least one lens 30 and a sensor 32. The lens 30 is suitable for focusing an optical flux, from the observed scene, onto the sensor 32. The sensor 32 is sensitive to the range of wavelengths observed (visible, infrared).

[0034] The rendering assembly 14 is suitable for rendering the optical flux captured in a range of wavelengths visible to a user.

[0035] The rendering assembly 14 includes a microscreen 34 and at least one eyepiece 36.

[0036] The microscreen 34 is designed to display an image according to the captured optical flow, the image displayed being in a range of wavelengths visible to the user (visible).

[0037] Each eyepiece 36 allows the user to view the image displayed by the microscreen 34.

[0038] In the case of binocular, binocular, or panoramic binoculars, the rendering assembly 14 comprises two eyepieces 36. Each eyepiece 36 is, for example, associated with a combination of optics 38 enabling the image to be projected projected by the microscreen 34 onto the eyepiece 36. This is notably the case in the examples of figures 2 and 3.

[0039] In the case of a monocular, the rendering assembly 14 comprises a single eyepiece 36. In this case, the image from the microscreen 34 is, for example, projected directly onto the eyepiece 36.

[0040] In one embodiment, each eyepiece 36 comprises optics contained within a metallic body, such as a metallic tube. The metallic body is isolated from the EMC (electromagnetic compatibility) shielding of the binoculars 10.

[0041] Preferably, as illustrated by embodiments in Figures 2 and 3, the binoculars 10 also include a portable power supply 40 and a user interface 42.

[0042] The portable power source 40 is, for example, a battery or a rechargeable cell.

[0043] The user interface 42 allows a user to make choices among the software menus of the binoculars 10. The user interface 42 includes, for example, one or more push buttons and / or a joystick.

[0044] The detection assembly 16 is suitable for detecting the proximity of a user to at least one of the eyepieces 36 (proximity is measured relative to the eyepieces 36 because they transmit the light from the microscreen and unintentionally illuminate the user's face). In particular, the detection assembly 16 is suitable for detecting the proximity of an element (user) located at a distance less than a predetermined distance from at least one of the eyepieces 36. The predetermined distance is, for example, equal to zero, meaning that proximity is detected when the user's face is against the eyepieces 36. Alternatively, the predetermined distance is, for example, equal to a few centimeters (e.g., 10 centimeters), meaning that proximity is detected as soon as the user's face is close to the eyepieces 36.As will be described later in the description, the predetermined distance depends on a predetermined sensitivity offset, and is optionally adjustable by a user.

[0045] The detection assembly 16 includes a capacitive sensor 50, a detection block 52 and a calibration block 54.

[0046] The capacitive sensor 50 is a proximity sensor. The capacitive sensor 50 comprises a metallic element that forms a capacitor with the user (the human body being conductive). At least one measuring electrode allows the capacitance of the capacitor thus formed to be measured.

[0047] The capacitive sensor 50 operates at low frequency where EMC radiation constraints are very low (below 100kHz, but above 20kHz to avoid any audible noise by piezoelectric effect).

[0048] The capacitive sensor 50 thus offers multiple advantages:

[0049] - an application area suitable for short distances,

[0050] - great discretion: no visible, near-infrared (NIR) or infrared radiation; very weak electromagnetic radiation (this being due to the presence of a variable signal on the capacitive electrodes) limited to Megahertz, considering that the radiation is negligible beyond the 10th harmonic of the operating frequency (to be moderated even further in the examples of figures 2 and 3, by the fact that the position of the sensor 50 makes this radiation directional towards the user during observation),

[0051] - very low consumption, making it possible to optimize the consumption of binoculars by turning off the microscreen 34.

[0052] The capacitive sensor 50 is positioned in the electronic binoculars 10 such that its capacitance fluctuates when a user approaches or moves away from it (in particular, approaches or moves away from an eyepiece 36). More precisely, the capacitance of the capacitive sensor 50 is the sum of a surrounding capacitance (related to its environment) and a possible capacitance related to the proximity between a user and this sensor 50.

[0053] Preferably, the capacitive sensor 50 is the metal body of the eyepiece or at least one of the eyepieces 36. This avoids adding a specific sensor on the rear face, thus simplifying the mechanical design of the binoculars 10. This example corresponds in particular to the embodiment of [Fig. 2]. In this case, the metal body has been properly isolated from the EMC (electromagnetic compatibility) shielding of the binoculars 10.

[0054] Alternatively, the capacitive sensor 50 is a dedicated sensor, separate from the eyepieces 36. The capacitive sensor 50 is, for example, a shielded metal plate. This alternative corresponds in particular to the embodiment of [Fig. 3].

[0055] The detection block 52 is suitable for detecting the proximity of a user to at least one of the eyepieces 36, depending on the capacity of the capacitive sensor 50 and a detection threshold.

[0056] Preferably, the detection block 52 is designed to detect the proximity of a user based on the phase variations of a signal internal to the detection block 52 and the detection threshold. The phase variations depend on the capacitance of the capacitive sensor 50. Taking into account the phase variations of an internal signal makes the detection robust to EMC interference. Indeed, an external, and therefore independent, signal cannot have exactly the same phase as an internal signal.

[0057] In what follows, we describe a preferred embodiment of the detection block 52.

[0058] In particular, in an example embodiment illustrated in [Fig. 4], the detection block 52 comprises an oscillator 60, a first phase shifter, called the detection phase shifter 62, a second phase shifter, called the reference phase shifter 64, and a swap- tillonneur 66.

[0059] The oscillator 60 is designed to generate a clock signal, referred to as the internal CLK signal.

[0060] The oscillator 60 operates at a low frequency where EMC radiation constraints are very low (below 100 kHz, but above 20 kHz to avoid any audible noise due to the piezoelectric effect). The oscillator frequency is, for example, 30 kHz.

[0061] The detection phase shifter 62 is designed to phase-shift the internal signal CLK according to the capacitance of the capacitive sensor 50, in order to obtain a SENSE detection signal. In the embodiment of [Fig. 4], the phase shift of the signal from the detection phase shifter 62 increases when the capacitance detected by the capacitive sensor 50 increases (and therefore increases when the user approaches the sensor).

[0062] In one example of implementation, the detection phase shifter 62 is formed from the capacitance of the capacitive sensor 50, a series resistor and a reshaping stage (signal reshaping).

[0063] The reference phase shifter 64 is designed to phase shift the internal signal CLK in an adjustable manner, to obtain a DCLK sampling signal. The adjustment of the reference phase shifter 64 is notably carried out according to the detection threshold.

[0064] In one embodiment, the reference phase shifter 64 consists of a capacitor, a series resistor, and a signal-shaping stage. At least one of these elements is variable, for example the resistor (so that the reference phase shifter 64 is adjustable).

[0065] The reference phase shifter 64 is adjusted so that the phase of the DLCK sampling signal is slightly greater than that of the SENSE detection signal, except in user proximity situations. The phase difference between the two is a sensitivity offset for proximity detection. The sensitivity offset thus fixes the predetermined distance between the user and the eyepieces 36, from which proximity detection is performed. When the capacitance picked up by the capacitive sensor 50 increases due to a user bringing their face closer, the phase shift of the SENSE detection signal increases until it exceeds that of the DLCK sampling signal (see timing diagram in [Fig. 4], period P2). Or, in other words, when a user brings their face closer, the phase shift variation of the SENSE detection signal increases until it exceeds the sensitivity offset.

[0066] The sampler 66 is suitable for sampling the SENSE detection signal from the DCLK sampling signal, to obtain an output signal Q. The output signal Q is suitable for taking two states such that: - when the phase of the SENSE detection signal is less than that of the DCLK sampling signal, the output signal Q is in a first state, indicating a lack of detected proximity, and - when the phase of the SENSE detection signal is greater than that of the DCLK sampling signal, the output signal Q is in a second state, indicating proximity detection.

[0067] For example, the sampler 66 is made with at least one D flip-flop.

[0068] Preferably, the sampler 66 is suitable for sampling the SENSE detection signal on both edges (at 0° and 180°) of the DCLK sampling signal.

[0069] Preferably, the detection block 52 further comprises a dual-time-constant filter 68. The filter 68 is used to validate the output signal Q of the detection block 52, indicating whether or not proximity has been detected, only after obtaining an output signal Q in the same state for a predetermined duration, which corresponds to a predetermined number of consecutive samples, performed by the sampler 66, in the same state. Thus, proximity detection is validated only if several consecutive samples of the SENSE detection signal, corresponding to the output signal Q in the second state, are obtained.

[0070] These two aspects ensure robustness against EMC interference. Indeed, if the SENSE detection signal originates from the internal CLK signal of the oscillator 60, the SENSE and DCLK signals have the same frequency, and the two out-of-phase samples of the sampler 66 always have complementary logic levels. If, on the other hand, the SENSE detection signal is disrupted by an EMC interference attempting to simulate the presence of the user, the two out-of-phase samples cannot remain at complementary levels in the long term, because the EMC interference is external to the system and cannot be correlated to the phase of the oscillator 60.

[0071] The dual-time-constant filter 68 confirms detection, particularly after a large number of consecutive 0° / 180° sampling pairs in the same state. The consecutive nature of the detection is achieved, on the one hand, by the "large" time constant, which allows for a large number of samplings in the same state, and, on the other hand, by the "small" time constant, which resets the filter 68 as soon as a 0° / 180° sampling pair does not exhibit complementary logic levels. The "large" time constant is chosen to be both much larger than the period of the oscillator 60 and small enough not to introduce a perceptible delay when the user brings their face close to the capacitive sensor 50. The "large" time constant is, for example, equal to 1000 periods of the oscillator 60, or 30 ms.

[0072] Preferably, the detection block 52 also includes a protection module 70 between the capacitive sensor 50 and the detection phase shifter 62. The protection module 70 is suitable for filtering high-frequency radiation (both internal and external). than external) and / or to provide protection against electrostatic discharge (ESD protection). ESD protection is useful because the capacitive sensor 50 is a conductive part accessible outside the binoculars 10 and electrically connected inside the binoculars 10.

[0073] We will now describe the calibration block 54 in what follows.

[0074] The calibration block 54 is designed to update the detection threshold in order to compensate for variations in surrounding capacitance. Variations in surrounding capacitance are, for example, due to variations in the dielectric permittivity of air as a function of pressure, temperature and humidity, but also to variations in the mechanical dimensions of the materials of the eyepieces 36 and the body of the binoculars 10 due to expansion.

[0075] The calibration block 54 is designed to perform the update only when no proximity is detected by the detection assembly 16, so that the detection threshold is fixed at its last value when proximity is detected. Thus, the calibration block 54 takes proximity detections into account to stop calibrations and does not compensate for a variation in capacity due to proximity. This is made possible by the fact that variations in surrounding capacity are very small during normal observation times through binoculars.

[0076] The detection threshold is therefore adjusted, by the calibration block 54, according to the surrounding capacitance and in the absence of a user near the eyepiece 36. This makes it possible to compensate for variations in surrounding capacitance.

[0077] In one embodiment, the calibration block 54 uses a calibration algorithm that measures the surrounding capacitance and forms the detection threshold by summing a moving average of this surrounding capacitance (in the absence of detection) and a sensitivity offset (a concept mentioned earlier in the context of the embodiment example of the detection block 52). The sensitivity offset is, for example, adjustable by a user so as to adjust the distance from which the detection block 52 detects proximity.

[0078] Preferably, the calibration block 54 is designed to update the detection threshold, not continuously, but at a predetermined frequency. The predetermined frequency is chosen so as to constitute an activation rate of the calibration algorithm much faster than the variations in surrounding capacitance and that, thus,

[0079] at each iteration, the amount of surrounding capacitance variation to be compensated is very small. For example, if we seek to compensate for surrounding capacitance variations due to temperature variations at a maximum rate of 3°C / min over a range of + / -60°C, with an 8-bit resolution, the predetermined frequency can, for example, be chosen to be 1 time every 10 seconds. In this example, and with this choice of At a predetermined frequency, the maximum temperature variation at each iteration of the calibration algorithm is 0.5°C, or 1.07 LSB (Least Significant Bit) of the range to be compensated. It is therefore possible, for example, to limit the calibration algorithm's compensations to a maximum of 2 LSB at each iteration.

[0080] This offers two advantages:

[0081] - on the one hand, this allows for a very short calibration time, which makes It is highly unlikely that calibration would start at the exact same time as proximity detection.

[0082] - on the other hand, if a calibration starts at exactly the same time as a Proximity detection (a single calibration is performed, as it is then locked as long as proximity is detected) results in a very small correction to the detection threshold due to calibration while the user is nearby. This correction does not significantly affect the sensitivity setting. Furthermore, the delay caused by calibration when the user wants to use the binoculars is very short and imperceptible to the human eye.

[0083] In particular, as shown in [Fig. 5], the calibration block 54 is clocked by a sequencer that activates the calibration algorithm at the desired rate. This algorithm allows the detection threshold to be formed by tracking the long-term variations of the capacitive signal (typically T2: slow variation of the surrounding capacitance over several tens of minutes). The detection sensitivity is configured by the offset introduced between the capacitive signal, excluding user proximity detections, and the detection threshold. The calibration algorithm takes proximity detections into account (T1: brief proximity, a few seconds; T3: long proximity, a few minutes) and, in this case, stops the calibrations so as not to compensate for a variation in capacitance due to proximity, which implies a detection threshold locked at its last value.

[0084] In the example of the detection block 52 detailed previously, the detection threshold corresponds to the setting of the reference phase shifter 64.

[0085] In one embodiment of the calibration block 54, it uses the internal signal CLK of the oscillator 60 to synchronize the application of corrections to the reference phase shifter 64, as well as the output signal Q of the sampler 66 to determine whether to increase or decrease the phase shift of the reference phase shifter 64 during the calibration phases.

[0086] Preferably, the calibration block 54 is designed to communicate with the control unit 18 (the main electronics of the binoculars 10) via a control / command link (typically a serial connection). This link allows the exchange of calibration information and enables the configuration of the sensitivity of the detection block 52. The proximity information of the user's face can be transmitted to the control unit 18 either via this serial connection or via a signal of specific interruption.

[0087] The control assembly 18 is suitable for controlling the display of the microscreen 34 according to the optical flux captured by the capture assembly 12 and the detection carried out by the detection assembly 16. In particular, the control assembly 18 is suitable for activating the microscreen 34 (the illumination of the microscreen 34) only when a proximity detection has been carried out by the detection assembly 16.

[0088] Thus, the detection unit 16 provides the proximity information of the user's face to the control unit 18 (the main electronics of the binoculars 10). The control unit 18 uses this information or not to control the illumination of the microscreen 34 depending on the software configuration.

[0089] In particular, the control assembly 18 is also suitable for carrying out the formatting of the information from the image sensor 32, the video processing and the execution of the software of the binoculars 10, as well as the formatting of the video information to the microscreen 34.

[0090] An example of the operation of the binoculars 10 will now be described, in particular in the context of proximity detection.

[0091] In the absence of a user near the eyepiece 36, the capacitance of the capacitive sensor 50 is solely due to the environment. As shown in [Fig. 4], the SENSE detection and DCLK reference signals are out of phase, such that the phase of the SENSE detection signal is lower than the phase of the DCLK sampling signal. Indeed, the phase shift of the SENSE detection signal is in this case solely due to the surrounding capacitance. The sampling of the SENSE detection signal by the DCLK sampling signal is such that the output signal Q of the sampler 66 is in its first state. This is particularly visible in the timing diagram of [Fig. 4] (period PI, the first state corresponds to the high state).

[0092] This lack of proximity detection is communicated by the detection assembly 16 to the control assembly 18, thus allowing the control assembly 18 to keep the microscreen 34 inactive, or to deactivate it if it was on.

[0093] During proximity detection, the phase of the SENSE detection signal is greater than the phase of the DCLK sampling signal. This is because the phase shift of the SENSE detection signal is due to the surrounding capacitance and, in addition, to a capacitance increased by the presence of the user. The sampling of the SENSE detection signal by the DCLK sampling signal is such that the output signal Q of the sampler 66 is in the second state. This is particularly visible on the timing diagram in [Fig. 4] (period P2, the second state corresponds to the low state). The state change is validated by the dual time-constant filter 68 (OUT signal) only after a time period P3. The period P3 is, for example, equal to 30 ms.

[0094] This proximity detection is communicated by the detection assembly 16 to the control assembly 18, thus enabling the control assembly 18 to activate the microscreen 34 or to continue to keep it active.

[0095] Thus, the detection assembly 16 detects the proximity of a user to one of the eyepieces 36 of the binoculars 10. This allows the control assembly 18 to automatically switch off the microscreen 34 of the binoculars 10 as soon as the user moves their face away from the binoculars 10 (or their eyes away from the eyepieces 36), so that the light from the microscreen 34 is not reflected onto their face, which would make them very easily visible at night. This function also optimizes the power consumption of the binoculars 10 by eliminating the power consumption of the microscreen 34 each time the user moves their eyes away.

[0096] The fact of fixing the detection threshold at its last value once a proximity has been detected allows detection of both long and short proximities, without detection error at the beginning or end of these proximities.

[0097] Capacitive proximity detection also has the advantage of being discreet: no visible, near-infrared (NIR) or infrared radiation, and very low electromagnetic radiation.

[0098] A person skilled in the art will understand that the embodiments and variants described above can be combined with each other provided that they are technically compatible.

Claims

1. Demands Electronic binoculars (10) comprising: - a capture unit (12) for an optical flow coming from a scene, - a restoration assembly (14) of the captured optical flow comprising: • a microscreen (34) designed to display an image according to the captured optical flow, and • at least one eyepiece (36) for viewing the image displayed by the microscreen (34), - a detection assembly (16) for the proximity of a user to at least one eyepiece (36), the detection assembly (16) comprising: • a capacitive sensor (50) positioned so that its capacitance fluctuates when a user approaches or moves away from it, said capacitance being the sum of a surrounding capacitance and a possible capacitance related to the proximity of the user, • a detection block (52) for the proximity of a user to at least one eyepiece (36) as a function of the capacity of the capacitive sensor (50) and a detection threshold, the detection threshold being set according to the surrounding capacity in the absence of detected proximity, and • a calibration block (54) designed to update the detection threshold to compensate for variations in surrounding capacity, the calibration block (54) being designed to perform the update only in the absence of proximity detected by the detection assembly (16) so that the detection threshold is fixed at its last value upon proximity detection, and - a control assembly (18) for the display of the microscreen (34) based on the optical flux captured by the capture assembly (12) and the detection performed by the detection assembly (16) so that the microscreen (34) is activated only when proximity is detected by the assembly detection (16).

2. Electronic binoculars (10) according to claim 1, wherein each eyepiece (36) is formed of a metallic body, the capacitive sensor (50) being the metallic body of the or at least one of the eyepieces (36).

3. Electronic binoculars (10) according to claim 1 or 2, wherein the detection block (52) is suitable for detecting proximity as a function of the phase variations of a signal internal to the detection block (52) and the detection threshold, the phase variations being a function of the capacitance of the capacitive sensor (50).

4. Electronic binoculars (10) according to any one of claims 1 to 3, wherein the detection block (52) comprises: - an oscillator (60) for generating a clock signal, referred to as the internal signal (CLK), - a phase shifter, referred to as the detection phase shifter (62), for shifting the phase of the internal signal (CLK) according to the capacitance of the capacitive sensor (50), to obtain a detection signal (SENSE), - a phase shifter, referred to as the reference phase shifter (64), for shifting the phase of the internal signal (CLK) in an adjustable manner, to obtain a sampling signal (DCLK), the reference phase shifter (64) being adjusted according to the detection threshold, - a sampler (66) for sampling the detection signal (SENSE) from the sampling signal (DCLK) to obtain an output signal (Q),The output signal (Q) is capable of taking two states such that: • when the phase of the detection signal (SENSE) is less than that of the sampling signal (DCLK), the output signal (Q) is in a first state, indicating no proximity detected, and • when the phase of the detection signal (SENSE) is greater than that of the sampling signal (DCLK), the output signal (Q) is in a second state, indicating proximity detection.

5. Electronic binoculars (10) according to claim 4, in which the sampler (66) is suitable for sampling the detection signal (SENSE) on both edges of the sampling signal (DCLK).

6. Electronic binoculars (10) according to claim 4 or 5, wherein the detection block (52) further comprises a dual time constant filter (68) suitable for validating the output signal (Q) indicating proximity detection or not, only after obtaining a predetermined number of consecutive samples of the detection signal (SENSE) giving an output signal (Q) in the same state.

7. Electronic binoculars (10) according to any one of claims 4 to 6, wherein the detection block (52) comprises a protection module (70) between the capacitive sensor (50) and the detection phase shifter (62), the protection module (70) being adapted to filter high-frequency radiation and / or to form protection against electrostatic discharges.

8. Electronic binoculars (10) according to any one of claims 1 to 7, wherein the detection threshold is formed by the sum of a moving average of the surrounding capacitance in the absence of detection and a sensitivity gap.

9. Electronic binoculars (10) according to claim 8, wherein the sensitivity gap is adjustable by a user so as to adjust the distance from which the detection block (52) detects proximity.

10. Electronic binoculars (10) according to any one of claims 1 to 9, wherein the calibration block (54) is suitable for updating the detection threshold at a predetermined frequency.

11. Electronic binoculars (10) according to any one of claims 1 to 10, wherein the electronic binoculars (10) are light-intensifying binoculars or thermal binoculars.

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