摘要:
The present invention relates to a method of operating a projection system comprising several solid state light sources (2, 3, 4) of different colour 13, 14, 15) and at least one spatial light modulator (1) having an array of switchable elements. Said array is illuminated by at least one of said light sources (2, 3, 4) for several illumination periods and is addressed such that the light is timely and spatially modulated to project images onto a screen. In the present method said light sources (2, 3, 4) are controlled to emit light modulated in amplitude (15) and/or time (18) during said illumination periods of said array. With the present method an increased greyscale resolution of the projection system can be achieved.
摘要:
A projection system for image reproduction by means of at least one lamp (10) as well as a sensor (30) for generating a sensor signal for monitoring changes in the luminous flux generated by said at least one lamp (10) and for compensating these changes through a suitable control of the image reproduction is described. The projection system comprises a device (31; 32; 36, 37) for eliminating substantially periodic interference components from the sensor signal generated by the at least one sensor (30; 301, 302, 303). These interference components may be generated by an optical component such as in particular a color modulator (12) of the projection system. The invention thus renders possible an at least substantially interference-free compensation of fluctuations in the luminous flux generated by the lamp (10), for example owing to an unstable arc discharge, also in those color systems in which the positioning of the sensor (30) in the projection system is non-critical.
摘要:
A projection system for image display with at least one lamp (1), with at least one sensor (5) for detecting changes in the luminous flux delivered by said at least one lamp (1) and for compensating these changes through a suitable control of the image display and/or the lamp is described. The projection system is remarkable in that a light integrator (3) is provided, into which at least a portion of the light provided by the lamp (1) is coupled in, while the sensor (5) is optically coupled to the light integrator (3) such that it detects the luminous intensity present in the light integrator (3). Since this luminous intensity is very homogeneous because of the multiple reflections and is not influenced by brightness fluctuations caused by an optical component such as, for example, a color modulator (4), a very accurate compensation of changes in the luminous flux generated by the lamp (1) is made possible by the sensor signal.
摘要:
The invention relates to a method for operating a discharge lamp 11 including two electrodes 12,13. The method comprises applying to the electrodes an alternating current ILamp. In order to improve the performance of the lamp and to increase the life time of the lamp, it is proposed that the alternating current has a direct current component DC for compensating a temperature difference between the two electrodes. The direct current component is selected more specifically such that a first electrode, which is expected to have a lower temperature than the second electrode, functions as anode for the direct current component, while the second electrode functions as cathode for the direct current component. The invention relates equally to an electronic circuit and to a software program for operating a discharge lamp correspondingly, as well as to a lighting system comprising a discharge lamp and means for operating this discharge lamp correspondingly.
摘要:
A method and a circuit arrangement for the operation of a high-pressure gas discharge lamp (HID [high intensity discharge] lamp or UHP [ultra high performance] lamp) is described, which lamp is particularly suitable for illuminating projection displays with sequential color rendering (for example LCOS or SCR-DMD systems) with a pulsatory lamp current. Artefacts in the color rendering are avoided through the generation of at least one compensation pulse of a given amplitude and a given timing and through superimposition thereof on the lamp current.
摘要:
A description is given of a method and a circuit arrangement for operating a high-pressure gas discharge lamp with a lamp current superposed with first current pulses, in particular in a system for the time-sequential production of (primary) colors and possibly white segments, from which an image to be displayed is synthesized, in which, in order to change or correct color and/or brightness properties of the image, the first current pulses are adjusted with regard to their amplitude and/or temporal length and/or temporal position relative to the production of the colors and/or white segments. A description is also given of a projection system comprising such a circuit arrangement.
摘要:
The invention relates to a projection system for image representation, with a display (61), at least one lamp (10), and at least one sensor (7) for generating a sensor signal for monitoring and compensating changes in the luminous flux provided by the at least one lamp (10). To achieve a monitoring of the light quantity actually incident on the display (61) which is as accurate and as interference-free as possible, an optical component (31) is arranged in a light path between the lamp (10) and the display (61), which component allows a first light component to pass through and reflects a second light component such that one of the light components is directed at the display (61) and the other light component is directed at the sensor (7) arranged outside the light path. A sensor signal generated in this manner renders it possible to compensate for fluctuations in the luminous flux provided by the lamp (10) through the control of a lamp driver (101) in an effective manner and practically without light losses and without being influenced by the brightness fluctuations generated by a color modulator or other components of the system.
摘要:
The invention relates to a high-pressure discharge lamp which comprises at least a burner (2) having a symmetrical discharge chamber (21), where at least the outer contour of the burner (2) has an elliptical shape in the region of the discharge chamber (21), two electrodes (41, 42) extending into the discharge chamber (21) and arranged in mutual opposition on the major axis of symmetry of the discharge chamber (21), and a multilayer interference filter (3) arranged on the outer contour of the burner (2) in the region of the discharge chamber (21), wherein the interference filter (3) mainly reflects light from at least one wavelength range of the UV light into the space between the two electrodes (41, 42).
摘要:
A lens plate integrator includes first and second lens plates which transmit light from a light source on an optical path to a projection plane. Each lens plate includes corresponding first and second groups of lens elements; light from the first group of the second plate is focused on a projection face in the projection plane, while light from the second group of the second plate is focused in front of or behind the projection plane and only partially illuminates the projection face.
摘要:
The invention relates to a measuring circuit for detecting the amount of deposited electrode material on the wall of a lamp vessel of a discharge lamp by measuring the power of infrared radiation within a specific wavelength range, comprising a detector for generating an electrical signal constituting a measure for the power of the infrared light in said specific wave length range. According to the invention the measuring is done in a time lapse starting after a predetermined time interval following the extinguishing of the discharge lamp. An increased accuracy of the measurement is thereby realized.