公开(公告)号：US3878107A

公开(公告)日：1975-04-15

申请号：US48266774

申请日：1974-06-24

Applicant: PHILCO FORD CORP

Inventor： PEMBROOK JOHN D ,  EDWARDS BYRON N ,  BURCH DARRELL E

IPC: G01J3/42 ,  G01N21/35 ,  G01N21/61 ,  G01N21/34

CPC classification number: G01N21/3518

Abstract: In a gas analyzer a beam of radiant energy is passed through a rotating gas cell which alternately inserts optically transmissive chambers into the path of the beam. One chamber contains a quantity of gas of the species to be analyzed at a pressure that produces sharp absorption lines. The other chamber is provided with either a quantity of gas at a pressure that produces substantial line broadening or a neutral density attenuator. In either case the chambers are made to have substantially equal average transmissivity over the spectral band of interest. The beam is then passed through a sample region in which the gas species concentration is to be measured. The beam is then detected by a photodetector. A filter, usually associated with the photodetector, limits the radiant energy response to a spectral region where the gas species to be measured displays suitable absorption lines. An electronic system amplifies the photodetector output and demodulates that signal component which occurs at a frequency corresponding to the cell rotation rate. In the absence of the particular gas in the sample region the two cell chambers have equal average transmissivity, and there should be no such component. However, if a quantity of the gas species to be measured is present in the sample region, a rotation rate signal component will be present and will be in proportion to the total quantity of that gas species in the sample region. In practice it is difficult to precisely balance the cell transmissivity values and, even if achieved, such balance is difficult to maintain. Accordingly the electronic amplifier is gain modulated at the cell rotation rate so that residual optical unbalance is corrected electrically. Since this correction is accomplished multiplicatively, it is independent of optical and electronic gain and loss values.

Abstract translation: 在气体分析仪中，辐射能量束通过旋转气室，其将光学透射室交替插入到光束的路径中。 一个室在产生尖锐吸收线的压力下含有一定量的待分析物质的气体。 另一个室设有一定量的气体，其压力产生大量的线宽度或中性密度衰减器。 在任一种情况下，室被制成在感兴趣的光谱带上具有基本相等的平均透射率。 然后将光束通过其中要测量气体种类浓度的样品区域。 光束然后由光电检测器检测。 通常与光电检测器相关联的滤光器将辐射能量响应限制在要测量的气体物质显示合适的吸收线的光谱区域。

公开(公告)号：US3916195A

公开(公告)日：1975-10-28

申请号：US47985974

申请日：1974-06-17

Applicant: PHILCO FORD CORP

Inventor： BURCH DARRELL E ,  PEMBROOK JOHN D

IPC: G01N21/61 ,  G01N21/35 ,  G01N21/34

CPC classification number: G01N21/3518

Abstract: A gas analyzer for measuring separately the quantities of two or more gas species present in a sample. The analyzer uses a rotating gas cell having a pair of chambers which are alternately inserted into a beam of radiant energy. At least one chamber contains a quantity of each of the gas species to be analyzed at suitable pressures. After passing through the rotating gas cell, the radiant energy is passed through the sample region and is then split into two or more beams by suitable optics. Each beam is passed through a band pass filter and sensed by a photodetector. Thus there will be a photodetector for each gas species to be measured and the associated filter is designed to have a bandpass that will admit radiant energy over a spectral region where the gas species displays suitable absorption lines. The electrical output from each photodetector can be analyzed electronically and related to the quantity of a particular gas species in the sample.

Abstract translation: 一种用于分别测量样品中存在的两种或更多种气体种类的量的气体分析仪。 分析仪使用具有交替插入辐射能束的一对室的旋转气室。 至少一个室在合适的压力下含有一定数量的待分析的气体物质。 通过旋转气体池后，辐射能通过样品区域，然后通过合适的光学元件分裂成两束或更多束。 每个光束通过带通滤光器并由光电检测器感测。 因此，将存在要测量的每种气体物质的光电检测器，并且将相关的过滤器设计成具有将在气体物质显示合适的吸收线的光谱区域上承受辐射能的带通。 每个光电检测器的电输出可以电子分析，并与样品中特定气体种类的数量相关。

公开(公告)号：US3926527A

公开(公告)日：1975-12-16

申请号：US47637374

申请日：1974-06-05

Applicant: PHILCO FORD CORP

Inventor： PEMBROOK JOHN D ,  BURCH DARRELL E ,  GATES FRANCIS J

IPC: G01N21/61 ,  G01N21/35 ,  G01N1/10 ,  G01J3/48

CPC classification number: G01N21/3518

Abstract: A rotating gas cell structure, intended for use in nondispersive electro-optical measurement equipment, includes at least a pair of chambers that, by virtue of rotation of the structure, are alternately inserted into a beam of radiant energy. The chambers contain a quantity of gas of the species to be analyzed at different pressure values. When used in a nondispersive radiant energy gas analyzer, the rotating cell will modulate the radiant energy in a way that permits a sensitive and accurate evaluation of a particular gas in a sample region. If desired the cell structure can include a built-in chopper to improve gas detection performance. In an alternate embodiment one of the chambers can be replaced by a radiant energy attenuator. Gas filling and sealing means for the cell chambers are disclosed.