Night vision device with integrated display

Abstract

The present invention relates to a night vision device comprising a binocular body (100) in which are mounted, along an optical axis, an objective lens (110), a light intensifier tube (190), a light guide (130), and an eyepiece lens (140), the light intensifier tube comprising a photocathode (121), a microchannel wafer (122), a phosphor screen (120) for providing a night vision image, and a light guide (130) having an entry face contiguous to the phosphor screen and an exit face for forming an image in the focal plane of the eyepiece lens. The light intensifier tube also comprises a display (260) in the form of a thin glass plate or thin film comprising light-emitting elements, the thin plate / film being arranged directly on the exit face of the light guide. A power supply and control module (250) housed within the tube body, at the periphery of the light guide, provides the respective bias voltages for the various components of the light intensifier tube and controls the luminescence of the light-emitting elements of the display.

Description

[0001] NIGHT VISION DEVICE WITH INTEGRATED DISPLAY

[0002] DESCRIPTION

[0003] TECHNICAL FIELD

[0004] The present invention relates generally to the field of night vision devices using a light intensifier tube (also called an image intensifier). It applies in particular to night vision binoculars (NVB).

[0005] STATE OF THE PRIOR ART

[0006] Night vision devices are generally used in low-light or even dark theaters of operation, in hostile environments, whether civilian or military. These night vision devices operate in the visible and near-infrared spectral range.

[0007] Fig. 1 schematically represents a conventional night vision device.

[0008] This is constructed from a binocular body, 100, within which are mounted along an optical axis, an objective, 110, a light intensifier tube, 190, and an eyepiece 140. The light intensifier tube 190 comprises a photocathode, 121, receiving the light having passed through the objective, and converting the photons thus received into photoelectrons, a microchannel plate or MCP, 122, acting as an electron multiplier by generating secondary electrons from the photoelectrons, a phosphor screen, 123, connected to an anode, converting the flow of secondary electrons into a luminous flux. An output optical guide, 130, generally consisting of a block of glass or a bundle of optical fibers attached to the phosphor screen, is intended to form an image in the focal plane of the eyepiece, 140.Finally, a power supply module 150 provides the supply voltages for polarizing the various constituent elements of the light intensifier tube. This power supply module is connected to a battery arranged outside the tube in question.

[0009] Since the user's concentration capacity is generally entirely mobilized by the observation of amplified images, it is difficult for them to disperse their attention across several terminals to take into account additional information (GPS data, route indicators, compass, alerts, etc.) likely to guide or help them in their mission.

[0010] In order to remedy this situation, it was proposed in patent US-B- 11054629 to integrate a micro-display into a conventional night vision device. This micro-display is arranged orthogonally to the optical axis of the tube, downstream from the light intensifier tube and upstream from the eyepiece. The image of the data display is projected onto a glass slide inclined at 45° (or a prism) on the optical axis of the tube. The projected image is combined with that received from the light intensifier tube and the user of the device then perceives the combination of the two images through the eyepiece.

[0011] Although this assembly effectively allows the image of a data display and that of a light intensifier tube to be combined within the same device, it cannot be obtained by simply renovating (retrofitting) an existing night vision device. Furthermore, the arrangement of the display at the tube output is not mechanically stable. Finally, the presence of the micro-display within the device, arranged orthogonally to the axis of the tube, reduces, by its size, the surface area of ​​the exit pupil and, consequently, the size of the image seen through the eyepiece.

[0012] Furthermore, when the output luminance of the light intensifier tube is low, the user of the night vision device may be dazzled by the display on the data screen. Therefore, it is necessary to balance the intensity of the display and that of the intensifier tube.

[0013] An object of the present invention is therefore to provide a night vision device which does not have the limitations of the state of the art, in particular which can be equipped with a display by simple renovation (retrofit), without modification of the focal lengths of the eyepiece and the objective, and without alteration of its performance, in particular without reduction of the size of the amplified images. A subsidiary aim of the present invention is to provide such a night vision device with an integrated display which maintains a good level of contrast between the night vision image and the image provided by the display. Finally, another aim of the invention is to provide a replacement light intensifier tube making it possible to renovate (retrofit) a conventional night vision device by transforming it into a night vision device with an integrated display.

[0014] STATEMENT OF THE INVENTION

[0015] The present invention is defined by a night vision device comprising a binocular body in which are mounted, along an optical axis, an objective, a light intensifier tube, and an eyepiece, the light intensifier tube comprising a photocathode intended to receive the light having passed through the objective and to convert the photons thus received into photoelectrons, a micro-channel plate intended to multiply the photoelectrons received from the photocathode by generating secondary electrons, a phosphor screen intended to provide a night vision image from the secondary electrons impacting it, an optical guide having an input face attached to the phosphor screen and an output face intended to form an image in the focal plane of the eyepiece,the night vision device being original in that the light intensifier tube further comprises a display in the form of a thin glass plate or a thin film comprising electroluminescent elements, the thin plate / thin film being arranged directly on the output face of the optical guide, a power supply and control module, housed within the light intensifier tube, on the periphery of the optical guide, intended to supply the respective bias voltages of the photocathode, the light intensifier and the phosphor screen and to control the electroluminescent elements of the display.,

[0016] The optical guide can be made up of a glass block or a bundle of optical fibers glued together.

[0017] According to a first embodiment, the display is produced by depositing a film on at least part of the output face, flat or planarized, the deposition being carried out by an atomic layer deposition (ALD) technique.

[0018] The thin film advantageously comprises a first dielectric layer, an electroluminescent film and a second dielectric layer, the assembly consisting of the first dielectric layer, the electroluminescent film and the second dielectric layer being sandwiched between a first network of electrodes arranged in the form of columns and a second network of transparent electrodes organized in lines, orthogonal to the first.

[0019] Electroluminescent elements can typically be presented in the form of segments.

[0020] According to a second embodiment, the display is produced by gluing a glass slide onto at least part of the output face, phosphor segments being deposited on the thin slide and individually addressable by conductive tracks.

[0021] Whatever the embodiment, according to a first variant, the power supply and control module is in the form of two separate units, a first unit having the function of supplying the respective high bias voltages of the photocathode, the micro-channel plate and the phosphor screen and a second unit having the function of controlling the display.

[0022] The night vision device may further comprise a communication module connected to the second unit by means of a bus, said communication module having a wireless radio interface, and providing information to be displayed to the second unit via said bus, said first unit transmitting to the second unit a signal (D) for controlling the luminance of the electroluminescent elements to be displayed.

[0023] In the first variant, the night vision device may further comprise a power supply module supplying low voltage to the first and second units, the first unit comprising a voltage multiplier for generating said high bias voltages from said low voltage.

[0024] In this case, the first unit measures the anode current of the phosphor screen and provides this measurement to the second unit, the second unit controlling the voltage and / or the duty cycle of a bias signal of the electroluminescent elements, so as to limit the ratio between the luminance of the elements thus displayed and the luminance of the night vision image to a level within a range of predetermined values.

[0025] The second unit advantageously controls the voltage and / or the duty cycle of the polarization signal of the electroluminescent elements so that the luminance of the latter varies in successive stages, the evolution of the luminance of the electroluminescent elements following with delay the evolution of the luminance of the night image when the latter increases or decreases.

[0026] The second unit can control the voltage and / or the duty cycle of the bias signal of the electroluminescent elements so that the luminance of the latter is proportional to the anode current filtered by means of a recursive low filter. Regardless of the aforementioned embodiment, in a second variant, the power supply and control module is in the form of an integrated unit, providing on the one hand the respective high bias voltages of the photocathode, the micro-channel plate and the phosphor screen, and controlling on the other hand the display.

[0027] In this case, said integrated unit is adapted to control the voltage and / or the duty cycle of the polarization signal of the electroluminescent elements so that the luminance of the latter is proportional to the anode current filtered by means of a recursive low filter.

[0028] The invention further relates to a replacement light intensifier tube, intended to renovate a night vision device, said night vision device comprising a binocular body in which are mounted, along an optical axis, an objective, a light intensifier tube, and an eyepiece, said replacement light intensifier tube being intended to replace the light intensifier tube and comprising a photocathode, intended to receive the light having passed through the objective and to convert the photons thus received into photoelectrons, a micro-channel plate intended to multiply the photoelectrons received from the photocathode by generating secondary electrons, a phosphor screen intended to provide a night vision image from the secondary electrons impacting it, an optical guide having an input face attached to the phosphor screen and an output face intended to form an image in the focal plane of the eyepiece,a display in the form of a thin glass plate or a thin film comprising electroluminescent elements, the thin plate / thin film being arranged directly on the output face of the replacement optical guide, said replacement light intensifier tube further comprising a power supply and control module intended to be housed within the body of the tube, on the periphery of the optical guide, and to provide the respective bias voltages of the photocathode, the light intensifier and the phosphor screen as well as to control the electroluminescent elements of the display.,

[0029] BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Other characteristics and advantages of the invention will appear on reading a preferred embodiment of the invention, made with reference to the attached figures among which:

[0031] Fig. 1 schematically represents a night vision device known from the state of the art;

[0032] Figs. 2A to 2D schematically represent different structural variants of a night vision device according to one embodiment of the invention;

[0033] Figs. 3A and 3B schematically represent two variants of a night vision device according to a first embodiment of the invention;

[0034] Figs. 3C and 3D schematically represent two variants of a night vision device according to a second embodiment of the invention;

[0035] Figs. 3E and 3F schematically represent the principle of contrast regulation in a night vision device, respectively according to the first and second embodiments of the invention;

[0036] Fig. 4 schematically represents different gain regimes of a light intensifier as a function of the input illumination level;

[0037] Fig. 5 schematically represents the control of the current of the segments of the display as a function of the anode current of a night vision device according to a particular embodiment of the invention. DETAILED DESCRIPTION OF PARTICULAR EMBODIMENTS

[0038] We will consider in the following a night vision device having the general structure presented in the state of the art.

[0039] In such a device, the input face of the optical guide is attached to the phosphor screen within the light intensifier tube, and the output face forms an image in the focal plane of the eyepiece.

[0040] The idea behind the present invention is to provide on the output face of the optical guide a display in the form of an electroluminescent thin blade / thin film.

[0041] This display allows information to be superimposed, for example location information, orientation, symbology, or tactical information, for example IFF (Identification Friend or Foe) type indications, like night vision.

[0042] Figs. 2A to 2D schematically represent different structural variants of a night vision device according to one embodiment of the invention.

[0043] For the sake of simplification, only the module consisting of the photocathode, the micro-channel plate and the phosphor screen, 220, the optical guide, 230, the display 260, and the power supply and control unit, 250, for powering and controlling the various elements of the light intensifier tube and the display, have been shown in these figures.

[0044] In all variants shown, the input face of the optical guide is attached to the phosphor screen of the light intensifier tube. The optical guide has an output face which does not necessarily extend over the entire output surface of the guide. The output face may be flat by construction (glass slide for example) or result from a mechanical or other planarization operation (block of optical fibers glued together for example). According to a first variant embodiment, shown in Fig. 2A and Fig. 2B, the display is made by a thin glass slide, attached to the output face of the optical guide. Phosphor segments are deposited on the thin slide and individually addressable by conductive tracks.

[0045] This thin blade can extend over the entire output section of the guide if it is flat (Fig. 2A) or a portion, or even the entire flat part of the latter. For example, in a second variant, the output surface can have a meniscus in its central part and a flat portion in its peripheral part. The thin blade is then fixed on the flat portion (Fig. 2B).

[0046] According to a second embodiment variant, shown in Fig. 2C and Fig. 2D, the display is produced by means of a thin electroluminescent film, deposited directly on the output face of the guide, either on the whole if the output section is flat (Fig. 2C), or a flat portion of it (Fig. 2D)

[0047] Advantageously, this film may be deposited by atomic thin film deposition (ALD) according to the method described in application US-A- 2019 / 0223268 incorporated herein by reference. This method comprises in particular the deposition of a first dielectric layer, the deposition of an electroluminescent layer of manganese-doped zinc sulfide (ZnS:Mn) on the first dielectric layer, and finally the deposition of a second dielectric layer on the luminescent layer. The first and second dielectric layers are transparent and are obtained for example by alternating alumina (AI2O3) sub-layers and zirconium oxide (ZrO2) sub-layers. The assembly consisting of the electroluminescent layer and the dielectric layers is sandwiched between a first network of transparent electrodes arranged in columns and a second network of transparent electrodes organized in lines, orthogonal to the first.A pixel or segment at the intersection of a column electrode and a row electrode is lit when a potential difference is applied between them. The display may be of the matrix type or of the segment type, in a manner known per se. Without prejudice to generalization, we will assume in the following that the display is segmented for reasons of simplification.

[0048] The thickness of the thin plate or thin film is chosen to be substantially less than the depth of field of the eyepiece so that the night vision image formed on the output face of the optical guide and the image generated by the display are both sharp (or have the same high degree of sharpness) and superimposed, as seen through the eyepiece. Thus, a single adjustment of the eyepiece allows the sharp observation of the night image and the displayed information.

[0049] For eyepieces commonly used in night vision binoculars, a blade / film thickness of the order of a few hundred microns can be chosen, preferably between 100 and 500 pm, typically equal to 300 pm.

[0050] Whatever the variant considered, the power supply and control module allows in particular the polarization of the segments of the electroluminescent film, according to the nature of the information to be displayed and the desired luminance characteristics.

[0051] Figs. 3A and 3B correspond to a first embodiment of the invention in which the power supply and control module is split into two separate units, 351, 352, respectively responsible for the high voltage power supply of the different elements of the light intensifier, and for the generation of the control signals for the display.

[0052] The high voltage power supply unit (HT PSU), 351, supplies the voltages HT1, HT2 and HT3 respectively to the photocathode, 321, the microchannel plate, 323, and the phosphor screen, 330, of the light intensifier tube. These high voltages are generated by a voltage multiplier, from a low voltage LV supplied by a single battery 350. The control unit, 352, controls the display 360, located directly on the output face of the optical guide, 330. This control unit can be powered by the battery 350 and receive information to be displayed from the power supply unit 351.

[0053] The variant of Fig. 3B differs from that of Fig. 3A in that the information to be displayed is received by an external communication module, 370, transmitting this information, for example via an I2C bus, if necessary after having decrypted it, to the control unit 352 which in turn translates it into control signals. These control signals control the display segments of the electroluminescent plate / film so as to form an image on the output face of the optical guide.

[0054] Figs. 3C and 3D correspond to a second embodiment of the invention in which the power supply and control module forms a single physical entity.

[0055] In other words, units 351 and 352 of Figs. 3A and 3B are integrated within a single unit, 355, located at the periphery of the optical guide as shown at 250 in Figs. 2A-2D.

[0056] In the first variant of the second embodiment, the unit 355 is autonomous. It generates the high voltages HT1, HT2 and HT3 for the different elements of the light intensifier tube from the low voltage supplied by a battery 350. For this purpose, the integrated unit 355 may comprise a voltage multiplier known per se. The integrated unit 355 further generates the control signals which control the different segments of the display 360.

[0057] In the second variant, the unit 355 receives the information to be displayed from the external communication module, 370, via an I2C bus. As in the first embodiment, the external communication module can receive the information to be displayed, if necessary in encrypted form, by means of a radio communication interface.

[0058] Regardless of the embodiment envisaged and the variant considered, the luminance of the display is advantageously controlled so as to maintain a limited contrast between the image of the display and the night vision image. More precisely, the ratio between the luminance (or brightness) of the displayed segments and the luminance of the night vision image is kept below a predetermined maximum value. Where appropriate, this same luminance ratio may also be kept above a predetermined threshold value.

[0059] Generally speaking, at constant illumination of the photocathode, the luminance of the night vision image is an increasing function of the anode current, l A , this depending essentially on the voltage across the micro-channel plate, V M CP, in other words in this case HT1 and HT2 and the duty cycle of the photocathode power supply.

[0060] The luminance of the segments is a function of the polarization voltage between the two electrode networks, from a few tens to a few hundred volts. This polarization signal is generally pulsed (with a recurrence frequency ranging from a few tens to a few thousand Hertz). By adjusting these two parameters (voltage level and duty cycle of the polarization signal) or even just one of them, it is possible to adjust the luminance of the display screen.

[0061] The principle of contrast control is shown in Figs. 3E and 3F, respectively for the first and second embodiments.

[0062] In the case of the first embodiment, the anode current l Ais read by the high voltage power supply unit 351 and this consequently provides a control signal regulating the polarization voltage of the electrode networks in addition to the control signals of the different segments, to ensure the desired contrast control.

[0063] In the case of the second embodiment, the anode current l A is read by the integrated unit 355 which then itself provides the polarization voltage of the electrode networks.

[0064] As previously indicated, the luminance of the displayed segments can be controlled by acting on the level of the bias voltage and / or its duty cycle.

[0065] Fig. 4 schematically represents the evolution of the anode current intensity, l A , depending on the illumination level of the photocathode.

[0066] This diagram shows different gain regimes depending on the level of illumination (also called night level) at the input of the light intensifier tube.

[0067] In a first regime, called linear regime, 410, for low night levels (i.e. low illumination levels), the high voltages applied to the microchannel plate and to the photocathode are fixed. The duty cycle of the voltage applied to the photocathode is also fixed, of the order of 100%. In this first regime, the anode current is proportional to the illumination level of the photocathode.

[0068] In a second regime, called saturation regime, 420, occurring at higher illumination levels, the luminance of the night vision image saturates at a predetermined maximum luminance level or MOB (Maximum Output Brightness). The luminance of the intensifier tube is maintained at said maximum level by acting both on the high voltage applied to the micro-channel plate and on the duty cycle of the pulsed voltage applied to the photocathode.

[0069] Whether in the linear regime or the saturation regime previously described, the voltage level (and / or duty cycle) of the segment polarization signal is controlled (are controlled) so that the contrast between the displayed image, more precisely the displayed segments, and the night vision image remains below a maximum value and advantageously within a range of predetermined values. According to a variant, this control is carried out so that the contrast level evolves in an interval centered on an average value, defined by a lower limit and an upper limit.

[0070] Fig. 5 schematically represents the evolution of the current within the display as a function of the anode current for a night vision device according to one embodiment of the invention.

[0071] The voltage level of the display bias signal is controlled so that the contrast level between the displayed image and the night vision image remains within an interval centered on an average value.

[0072] We can again distinguish between the two operating modes of the light intensifier.

[0073] In the saturation regime, 520, the amplitude of the bias voltage (and / or the duty cycle of the bias signal when it is pulsed) is kept substantially constant so as to respect a set contrast level, S. This set level can be set to a value predetermined by the manufacturer or adjusted by the user according to his visual comfort. The level (and where appropriate the duty cycle in the case of a pulsed signal) of the bias voltage of the segments of the display is set so as to obtain the set contrast level. In this case, the current between the two electrodes polarizing a segment is such that seg = IF A When the polarization signal is pulsed, the average current of the segment must be taken into account instead of the instantaneous current.

[0074] In the linear regime, 510, it is also possible to control the level of the bias voltage (and / or its duty cycle) so as to ensure the relationship l seg = IF A . However, to avoid excessively rapid fluctuations in Iseg when the luminance of the night image varies (dynamic image, user or moving target), it may be appropriate to vary the intensity only seg than in successive stages. In other words, the variations in intensity seg will be able to follow the variations of the anode current only with a delay, the successive stages then being different depending on whether the luminance of the night image increases or decreases. The hysteresis cycles corresponding to the different stages are illustrated in Fig. 5.

[0075] Alternatively, the voltage level and / or duty cycle of the bias signal will be adjusted so that the seg = S.LP(I A ) where LP(I A) is the anode current filtered by a low-pass filter, advantageously by a first-order recursive low-pass filter. The forgetting coefficient of the recursive filter can, again, be set to a value predetermined by the manufacturer or adjusted by the user.

[0076] The person skilled in the art will finally understand that the invention also relates to a replacement tube, with an integrated display, making it possible to easily renovate a conventional night vision device, such as that shown in Fig. 1, into a night vision device such as those shown in Figs 2A-2D.

[0077] More specifically, this integrated display tube replaces a standard tube in the night vision device. The integrated display tube comprises a photocathode, a microchannel plate, a phosphor screen, and an optical guide at the output of the latter intended to form an image in the focal plane of the eyepiece. It further comprises a power supply and control module intended to be housed within the body of the tube, on the periphery of the optical guide, to provide the respective bias voltages of the photocathode, the light intensifier, and the phosphor screen, and to control the electroluminescent elements of the display.

Claims

DEMANDS 1. Night vision device comprising a binocular body (100) in which are mounted, along an optical axis, an objective lens (110), a light intensifier tube (190), and an eyepiece (140), the light intensifier tube (190) comprising a photocathode (121) for receiving the light that has passed through the objective lens and for converting the photons thus received into photoelectrons, a micro-channel plate (122) for multiplying the photoelectrons received from the photocathode by generating secondary electrons, a phosphor screen (123) for providing a night vision image from the secondary electrons impacting it, an optical guide (130) having an entrance face adjacent to the phosphor screen and an exit face for forming an image in the focal plane of the eyepiece,The night vision device is characterized in that the light intensifier tube further comprises a display (260) in the form of a thin glass plate or a thin film having electroluminescent elements, the thin plate / thin film being disposed directly on the output face of the optical guide, a power supply and control module (250), housed within the light intensifier tube, on the periphery of the optical guide, intended to provide the respective bias voltages of the photocathode, the light intensifier and the phosphor screen and to control the electroluminescent elements of the display.

2. Night vision device according to claim 1, characterized in that the optical guide is constituted by a glass block or by a bundle of optical fibers glued together.

3. Night vision arrangement according to claim 1 or 2, characterized in that the display is made by depositing a film on at least a part of the output face, flat or planarized, the deposit being made by an atomic layer deposition (ALD) technique.

4. Night vision device according to claim 3, characterized in that the thin film comprises a first dielectric layer, an electroluminescent film and a second dielectric layer, the assembly consisting of the first dielectric layer, the electroluminescent film and the second dielectric layer being sandwiched between a first network of electrodes arranged in columns and a second network of transparent electrodes arranged in lines, orthogonal to the first.

5. Night vision device according to claim 2, characterized in that the electroluminescent elements are in the form of segments.

6. Night vision device according to claim 5, characterized in that the display is made by bonding a glass plate to at least part of the output face, phosphor segments being deposited on the thin plate and individually addressable by conductive tracks.

7. Night vision device according to any one of the preceding claims, characterized in that the power supply and control module is in the form of two separate units (351, 352), a first unit (351) having the function of providing the respective high bias voltages of the photocathode, the micro-channel wafer and the phosphor screen and a second unit (352) having the function of controlling the display.

8. Night vision device according to claim 7, characterized in that it further comprises a communication module (370) connected to the second unit (352) by means of a bus, said communication module having a wireless radio interface, and providing information to be displayed to the second unit via said bus, said first unit transmitting to the second unit a signal (D) for controlling the luminance of the electroluminescent elements to be displayed.

9. Night vision device according to claim 8, characterized in that it further comprises a power supply module (350) supplying low voltage to the first and second units, the first unit comprising a voltage multiplier to generate said high bias voltages from said low voltage.

10. Night vision device according to claim 9, characterized in that the first unit measures the anode current of the phosphor screen and provides this measurement to the second unit, the second unit controlling the voltage and / or duty cycle of a biasing signal of the electroluminescent elements, so as to limit the ratio between the luminance of the elements thus displayed and the luminance of the night vision image to a level within a range of predetermined values.

11. Night vision device according to claim 10, characterized in that the second unit controls the voltage and / or the duty cycle of the polarization signal of the electroluminescent elements so that the luminance of the latter varies in successive steps, the evolution of the luminance of the electroluminescent elements following with a delay the evolution of the luminance of the night image when the latter increases or decreases.

12. Night vision device according to claim 10, characterized in that the second unit controls the voltage and / or duty cycle of the polarization signal of the electroluminescent elements so that the luminance of the latter is proportional to the anode current filtered by means of a low recursive filter.

13. Night vision device according to any one of claims 1 to 6, characterized in that the power supply and control module is in the form of an integrated unit (351, 352), providing on the one hand the respective high bias voltages of the photocathode, the micro-channel wafer and the phosphor screen, and on the other hand controlling the display.

14. Night vision device according to claim 13, characterized in that said integrated unit is adapted to control the voltage and / or duty cycle of the polarization signal of the electroluminescent elements so that the luminance of the latter is proportional to the anode current filtered by means of a low recursive filter.

15. A replacement image intensifier tube for upgrading a night vision device, said night vision device comprising a binocular body (100) in which are mounted, along an optical axis, an objective lens (110), an image intensifier tube (190), and an eyepiece (140), said replacement image intensifier tube being intended to replace the image intensifier tube and comprising a photocathode (121) for receiving light that has passed through the objective lens and for converting the photons thus received into photoelectrons, a microchannel plate (122) for multiplying the photoelectrons received from the photocathode by generating secondary electrons, a phosphor screen (123) for providing a night vision image from the secondary electrons impacting it, and a guide 20 optics (130) having an input face attached to the phosphor screen and an output face intended to form an image in the focal plane of the eyepiece, a display (260) in the form of a thin glass plate or a thin film comprising electroluminescent elements, the thin plate / thin film being disposed directly on the output face of the replacement optical guide, said replacement light intensifier tube further comprising a power supply and control module (250) intended to be housed within the body of the tube, on the periphery of the optical guide, and to provide the respective bias voltages of the photocathode, the light intensifier and the phosphor screen as well as to control the electroluminescent elements of the display.

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