concurring in part and dissenting in part.
While I agree with the majority that claim. 10, on the record before us, would have been obvious at the time the invention was made under 35 USC 103,1 would reverse the decision of the Patent Office rejecting claim 9 on the same statutory basis. Initially, I believe that additional background material relative to appellants’ invention should be set forth, including a discussion of the problem faced by appellants in making this invention, to provide a broader understanding of the basis for my disagreement with the maj ority.
As appellants state, the invention relates to a mass spectrometer beam definition device which may be used in 'a constant velocity, “right angle entry” mass spectrometer system. A right angle entry system, which appellants admit is known to the art, is one in which the source particles are introduced into the spectrometer in a direction which is generally normal to the accelerating direction. A purpose of such systems is to minimize the presence of background ions in the detected output of the spectrometer. As appellants’ specification states:
* ⅜ ⅜ The background ions are accelerated substantially in the direction of the accelerating field while the source particles are accelerated along a direction which is a combination or resultant of the initial entry velocity and the accelerating field and in this manner the two groups may be distinguished by placing a collector only in the resultant direction.
A problem in this art and appellants’ solution to the problem is described in the specification in the following terms:
One difficulty arising in this method of depressing 'background ions is that the resultant direction of the heavy source partidles is slightly different than that for the 'lighter source particles so that .the resultant beam of source particles is divergent. This is undesirable since it makes it more difficult .to distinguish *735from the 'background ions and ailso some of 'the source particles may be lost due to the divergency.
This invention alleviates this problem by applying energy to a deflecting device 'through which the resultant beam passes in such a manner so as to maintain the beam definition by substantially eliminating the aforementioned divergency.
The appellants have arguably distinguished their device in two respects: ( a) the nature of the field provided by the deflecting device, and (b) the characteristics of the source particles.
As to these distinctions, appellants explain that the deflecting device may provide either an electric or an electromagnetic field through which the beam of source particles passes. To establish a deflecting electrjfc .field, a voltage is provided between a pair of parallel plates between which the particles pass on their path to the detector. The characteristics of the applied voltage depend on the characteristics of the entering source particles. Appellants urge that if the energy of the source particles is constant, such as would be the case when particles are obtained from a solid source by heating and sublimation, a constant voltage would maintain the beam definition if the voltage were related to the constant energy. Since the energy of different particles is the same, heavier particles are slower, and lighter particles are faster.
On the other hand, if the source particles have a constant velocity, appellants state, such as would occur if they were obtained by a satellite measuring the atmosphere, a variable voltage across the parallel deflecting plates would maintain beam definition. In this instance, beam definition is provided by 'higher voltage applied to the deflecting plates as the heavier, slower ions pass between the plates to deflect these ions more than the lighter ions. Both the heavier and lighter ions have, of course, entered the system at the same velocity, but the result of the accelerating field, in a direction normal to the direction of entry, on the speed of the particles differs.
As to the first embodiment, appellants’ brief urges that previous systems have used constant voltage fields for constant energy source particles while the invention uses a variable voltage field for conver-gency of constant velocity source particles. The appellants’ choice of this terminology may be somewhat unfortunate since claim 9 asserts in part that:
⅜ ⅜ ⅜ Saicl control means comprising means for applying an increasing electric field in a direction having components transverse to said resultant direction to apply a correction force to said particles to minimize the divergency of said particles. [Emphasis added.]
In order to grasp more significantly the meaning of this language as used in the claim, it is necessary to consider certain portions of *736appellants’ specification, as we must under United States v. Adams, 383 U.S. 39 (1966) where the Supreme Court specifically pointed out, Id. at 48-49, that :
* * * -while the claims of a patent limit the invention, 'and specifications cannot be utilized to expand the patent monopoly * * * it is fundamental- that claims are to be construed in the light of the specification and both are to be read with a view to ascertaining the invention * ⅜ *. [Citations omitted.]
Thus, on the characteristics of the voltage applied to the deflecting plates for deflecting the accelerated particles, appellants state:
* * * The higher energy particles would have a different accelerated direction, than the lower energy partidles 'and this can be compensated for by voltage source 42a putting a varying voltage on the deflecting plates 41a. The voltage is synchronized with the pulses applied to grids 28a and 30a and increases with, time as the ions were traveling by during a single deceleration period, and the lighter, lesser energy ions do not get as much deflecting voltage as the later heavier, larger energy ions. [Emphasis added.] * * *
Thus, reading that portion of the claim pertinent to this discussion in light of the specification, it is clear that the voltage applied to the parallel plates must (1) be synchronized with the pulses applied to the accelerating means to provide the accelerating field and (2) increase with time as the ions pass between the plates during a single acceleration period.
The examiner, in both his final rejection and his answer on appeal, and the board itself, seem to have considered claim 9 as defining a variable voltage, contrary to the expressed wording of the claim and the explanations of the specification. In his answer the examiner states:
* * * claim 9 sets forth the embodiment of Fig. 4 of appellants’ drawings which employs a control means comprising a variable voltage applied to the plates to provide a variable electrostatic field. The secondary patent to Schroeder shows that electrostatic fields may be constant (Figs. 14 to 16) or variable (Figs. 19 and 21) and may be used alternately to produce the separation of ions. It is obvious that such relationship exists for the control means of the type disclosed by appellants and Benson et al. Therefore, it would be obvious to one of ordinary skill in the art to employ the variable electrostatic field control means shown in Figs. 19 and 21 of Schroeder in place of the constant electrostatic field control means 135 (Fig. 7) of Benson et al. * * *
The solicitor’s brief describes the Schroeder reference in detail, but as to its teaching of the nature of the voltage to be applied to the deflecting plates, states:
* * * Also, a pulsating voltage may be applied to electrostatic deflection electrodes to deflect the ions. * * *
The Schroeder patent describes the embodiments on which the solicitor relies as including a relatively short duration, accelerating pulse applied to the accelerating electrode. A similar deflecting pulse of short time duration and synchronized with the accelerating pulses is *737described as being utilized to provide selective deflection of ions of a predetermined atomic weight m order that the abundance of such ions may be measured by a target electrode. Figs. 19 and 21 of the Sehroeder patent disclose conventional “square wave” pulse waveforms applied to the deflecting plates. Nowhere in the reference does there appear a teaching that the pulse is an “increasing” pulse to provide an “increasing electric field” as claimed, and as described in the specification as increasing with time during a single acceleration period.
It is arguable that the leading edge of any one pulsé, as illustrated in Sehroeder, as applied to the deflecting plates, may be considered an increasing voltage to provide the claimed “increasing electric field.” This position, however, it seems to me, does not meet a reasonable construction of the claim, in the light of the specification which requires that the pulse increase with time during a single acceleration period. It would seem that appellants’ contribution to the art, not shown by •the references of record before us, is that of providing an increasing, rather than an increased electric field between the deflecting plates to achieve particle convergence. Such a concept is not taught by the application of a constant magnitude pulse during any one acceleration period, as taught by the Sehroeder reference. On this basis, I do not think that claim 9 thus considered as a whole would have been obvious within the meaning of section 103.
The board stated :
* * * In our opinion it would, be within the skill o-f the ant to feed the plates of the [Benson] ¡reference through a rheostat to obtain any desired voltage betwteen the plates particularly in view of column 8 of Sehroeder. Benson et al., modified in this obvious ¡manner, meets the structural limitations of claim 9 (Brackets added).
I do not think that, within the clear expression of the appellants’ terms and disclosure, merely providing a device to meet “structural limitations” of claim 9 meets the statutory requirements for probative inquiry into an issue of obviousness. We deal here with the invention defined by claims construed in the light of the specification. The invention thus ascertained is not, in my view, made obvious by the selection of apparatus in the light of appellants’ teachings which may be said to “meet” such “structural limitations.”
The critical portion of appellants’ combination claim 9 is expressed as a means for performing a specified function, statutorily permitted under 35 TJSC 112. It seems that the «board is criticizing the language of the claim, perhaps intimating that Ae language used is so “broad” that it differs from the references only by the provision of a rheostat. Initially, I observe no teaching in the references that «a rheostat would *738provide the claimed function, nor any teaching that, if provided, a rheostat would be likely to apply an electric field increasing in time during a single acceleration period. Nor does it seem to me that the provision of a rheostat would necessarily minimize the divergency of the particles. Thus, I do not think that appellants’ claimed invention as a whole, as claimed in claim 9, would have 'been obvious to one of ordinary skill in the art at the time it was made. Accordingly, I would reverse the decision of the board affirming claim 9.
On the other hand, I concur in the majority’s affirmance of the decision of the board as to claim 10 for the reasons stated in the majority opinion.